# could / was able to



## Akasaka

Hello everyone,
I still don't understand the difference between "was able to" and "could." Can I use "could" instead of "was able to" in this sentence?
After a lot of practice he *could *understand English.

Thanks in advance.


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## nichec

Akasaka said:


> Hello everyone,
> I still don't understand the difference between "was able to" and "could." Can I use "could" instead of "was able to" in this sentence?
> After a lot of practice he *could *understand English.
> 
> Thanks in advance.


 
Yes, you can.


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## liliput

Generally speaking, we use the irregular form "could" when referring to a general ability - "John Wayne could ride a horse" - and "was/were able to" when referring to a specific instance - "I was able to study English last weekend."
In some cases they are interchangeable, but this is a good general rule. Your sentence could be interpreted as a general ability but actually you are referring to a specific time (after a lot of practise) so the sentence sounds better with "was able to".


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## nichec

liliput said:


> Generally speaking, we use the irregular form "could" when referring to a general ability - "John Wayne could ride a horse" - and "was/were able to" when referring to a specific instance - "I was able to study English last weekend."
> In some cases they are interchangeable, but this is a good general rule. Your sentence could be interpreted as a general ability but actually you are referring to a specific time (after a lot of practise) so the sentence sounds better with "was able to".


 
Yes, it sounds better with "was able to", but "could" is acceptable, right?


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## liliput

nichec said:


> Yes, it sounds better with "was able to", but "could" is acceptable, right?


 
It's OK, but it sounds a little odd.


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## nichec

liliput said:


> It's OK, but it sounds a little odd.


 

Hmmmm........Perhaps an AE/BE difference.........


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## Akasaka

liliput said:


> Generally speaking, we use the irregular form "could" when referring to a general ability - "John Wayne could ride a horse" - and "was/were able to" when referring to a specific instance - "I was able to study English last weekend."


Thank you very much for giving me this rule, which is clearer than the one written in my grammar book.
I also wonder where this difference come from. Why can't "could" refer to a specific instance?


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## liliput

Akasaka said:


> Thank you very much for giving me this rule, which is clearer than the one written in my grammar book.
> I also wonder where this difference come from. Why can't "could" refer to a specific instance?


 
I'm not sure exactly. It's certainly worth mentioning that strictly speaking the past tense of "to be able to" is "was/were able to". "Could" should really only be used for the conditional (although it's common practice to use it in the past tense). Perhaps that's why it's always possible to use "was/were able to" for any past sentence but some sentences sound odd with "could". For example, I can say "John Wayne was able to ride a horse" or "John Wayne could ride a horse" and both sound fine, but "I could study last weekend" doesn't sound right - it has to be "I was able to study last weekend".
I suspect that Nichec may be right and there is an AE/BE difference. For AE speakers "I could study last weekend" may not sound so strange.


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## nichec

liliput said:


> I'm not sure exactly. It's certainly worth mentioning that strictly speaking the past tense of "to be able to" is "was/were able to". "Could" should really only be used for the conditional (although it's common practice to use it in the past tense). Perhaps that's why it's always possible to use "was/were able to" for any past sentence but some sentences sound odd with "could". For example, I can say "John Wayne was able to ride a horse" or "John Wayne could ride a horse" and both sound fine, but "I could study last weekend" doesn't sound right - it has to be "I was able to study last weekend".
> I suspect that Nichec may be right and there is an AE/BE difference. For AE speakers "I could study last weekend" may not sound so strange.


 
Sorry, "he could understand English" sounds okay to me, but not "I could study last weekend".


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## liliput

nichec said:


> Sorry, "he could understand English" sounds okay to me, but not "I could study last weekend".


 
Yes Nichec, the "understand English" example is not so clear-cut because it refers both to a general ability and a specific time. I have noticed that some AE speakers seem to find the "could" form acceptable in all (or almost all) cases, but perhaps they are the exception rather than the rule.


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## se16teddy

_After a lot of practice he could understand English_ and _After a lot of practice he was able to understand English_ both sound fine to me. I think that _could understand _and _was able to understand _can both refer to a moment of revelation (perfective use), and can also refer to an established ability (imperfective use).


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## liliput

se16teddy said:


> _After a lot of practice he could understand English_ and _After a lot of practice he was able to understand English_ both sound fine to me. I think that _could understand _and _was able to understand _can both refer to a moment of revelation (perfective use), and can also refer to an established ability (imperfective use).


 
What about "I could study last weekend" and "I was able to study last weekend"? Do they both sound equally correct to you? Do you have a preference? Do they carry exactly the same meaning? 
(No criticism intended, I'm just curious to know if it's only my perception.)


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## se16teddy

liliput said:


> What about "I could study last weekend" and "I was able to study last weekend"? Do they both sound equally correct to you? Do you have a preference? Do they carry exactly the same meaning?
> (No criticism intended, I'm just curious to know if it's only my perception.)


_The gas men were drilling the road last weekend but I could study because I went to my Gran's. _
_The gas men were drilling the road last weekend but I was able to study because I went to my Gran's._
Both these sound fine to me.  The first is a bit better because it is snappier.


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## liliput

se16teddy said:


> _The gas men were drilling the road last weekend but I could study because I went to my Gran's. _
> _The gas men were drilling the road last weekend but I was able to study because I went to my Gran's._
> Both these sound fine to me. The first is a bit better because it is snappier.


 
For me, "I could study" means I had a general ability to study, which I now don't have; whereas "I was able to study" means I found the time/place/conditions in which it was possible to study.


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## Dimcl

liliput said:


> For me, "I could study" means I had a general ability to study, which I now don't have; whereas "I was able to study" means I found the time/place/conditions in which it was possible to study.


 
I agree.  The *specific ability* to study at that point in time seems lost in:

_The gas men were drilling the road last weekend but I could study because I went to my Gran's. _

In this sentence, "could" sounds odd to me because it's not specific.  It would never occur to me to use "could" in this context because it almost sounds like I could have (but did I?).


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## liliput

Dimcl said:


> I agree. The *specific ability* to study at that point in time seems lost in:
> 
> _The gas men were drilling the road last weekend but I could study because I went to my Gran's. _
> 
> In this sentence, "could" sounds odd to me because it's not specific. It would never occur to me to use "could" in this context because it almost sounds like I could have (but did I?).


 
An interesting point this last one. Perhaps that's why I don't have the same problem with the negative: "I couldn't study last weekend", "I couldn't go to the party last Friday" and "I couldn't sleep last night" all seem the same as with "wasn't able to". I only note the difference with the positive form.


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## cheshire

Dimcl said:


> I agree.  The specific ability to study at that point in time seems lost in:
> 
> _The gas men were drilling the road last weekend but I could study because I went to my Gran's. _
> 
> In this sentence, "could" sounds odd to me because it's not specific.  It would never occur to me to use "could" in this context because* it almost sounds like I could have (but did I?)*.


I'm really sorry, but could anybody rewrite the bold part for me to understand?


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## sound shift

I remember Arsène Wenger, manager of Arsenal FC, speaking to a reporter after his team had won a match. He said,
_I'm glad we could win_.

What he said sounded wrong to me. I would have said,
_I'm glad we won _or
_I'm glad we were able to win._


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## cheshire

sound shift said:


> I remember Arsène Wenger, manager of Arsenal FC, speaking to a reporter after his team had won a match. He said,
> _I'm glad we could win_.
> 
> What he said sounded wrong to me. I would have said,
> _I'm glad we won _or
> _I'm glad we were able to win._


Can we ascribe the "defense mechanism" some of you've shown here on this thread to the possible ambiguity, i.e. the past ability/availability/possibility with the present subjunctive ability/availability/possibility?


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## Thomas Tompion

cheshire said:


> I'm really sorry, but could anybody rewrite the bold part for me to understand?


 
_



			The gas men were drilling the road last weekend but I could study because I went to my Gran's.
		
Click to expand...

_


> In this sentence, "could" sounds odd to me because it's not specific. It would never occur to me to use "could" in this context because* it almost sounds like I could have (but did I?)*.


 
I've rather lost track who said the quote above, but Cheshire asked for it to be rewritten, so here goes.

It would never occur to me to use 'could' in this context because, putting it like that makes it appear that I might have been able to study, without specifying whether I actually did or didn't.

I'm not asking for any prizes for the style of the translation - I've deliberately spelled this out at some length, in the hope of being clear. 

I don't actually agree with the sentence as an interpretation of 'could' in the sentence about the gas men, but that's as maybe.


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## dn88

sound shift said:


> I remember Arsène Wenger, manager of Arsenal FC, speaking to a reporter after his team had won a match. He said,
> _I'm glad we could win_.
> 
> What he said sounded wrong to me. I would have said,
> _I'm glad we won _or
> _I'm glad we were able to win._



To me, a non-native speaker, the difference is as follows:

1) *I'm glad we could win.* - I suppose that the opponent wasn't very strong, probably there were also some other factors leading to victory besides the players' ability to win the game (that's just my first impression though)

2)_ *I'm glad we were able to win.* - _I draw the conclusion that the players were skilled enough to win against their opponent (that's the main reason why they won the match and, perhaps, there are no other factors)

Looking at some of the opinions, I guess I should interprete it the other way round. Anyway, now I'm confessing my first thoughts. And if I'm honest, the latter sentence sounds... errrr... strange (because it's longer??)


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## Thomas Tompion

dn88 said:


> To me, a non-native speaker, the difference is as follows:
> 
> 1) *I'm glad we could win.* - I suppose that the opponent wasn't very strong, probably there were also some other factors leading to victory besides the players' ability to win the game (that's just my first impression though)
> 
> 2)_ *I'm glad we were able to win.* - _I draw the conclusion that the players were skilled enough to win against their opponent (that's the main reason why they won the match and, perhaps, there are no other factors)
> 
> Looking at some of the opinions, I guess I should interprete it the other way round. Anyway, now I'm confessing my first thoughts. And if I'm honest, the latter sentence sounds... errrr... strange (because it's longer??)


Wenger speaks like a foreigner; like and educated and articulate foreigner, I admit, but I think it's unwise to come to any conclusions about English idiom from the words he has chosen.

For what it's worth, I, a native speaker of BE, wouldn't draw any significant difference in meaning from the two different forms of words.


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## dn88

Thomas Tompion said:


> Wenger speaks like a foreigner; like and educated and articulate foreigner, I admit, but I think it's unwise to come to any conclusions about English idiom from the words he has chosen.
> 
> For what it's worth, I, a native speaker of BE, wouldn't draw any significant difference in meaning from the two different forms of words.



I didn't focus on the person who had said that, I was trying to find a difference from a purely grammatical/semantic point of view.


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## liliput

sound shift said:


> I remember Arsène Wenger, manager of Arsenal FC, speaking to a reporter after his team had won a match. He said,
> _I'm glad we could win_.
> 
> What he said sounded wrong to me. I would have said,
> _I'm glad we won _or
> _I'm glad we were able to win._


 
I agree. It sounds wrong to me and I think it's because _could _is the conditional form. It sounds like they haven't won yet - "We could win" = "We have the possibility of winning". It sounds much better, and is technically more correct, to say "we were able to win".


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## Thomas Tompion

liliput said:


> I agree. It sounds wrong to me and I think it's because _could _is the conditional form. It sounds like they haven't won yet - "We could win" = "We have the possibility of winning". It sounds much better, and is technically more correct, to say "we were able to win".


 
Hi Liliput, but don't we say every day things like: I'm so glad you could come - after the person has arrived - there's no question of the person's not having come yet.  One hears it from the hostess at many parties.

I'm not convinced, you see, that this is the conditional at all.  It seems to me the simple past, like were able to.


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## liliput

Thomas Tompion said:


> Hi Liliput, but don't we say every day things like: I'm so glad you could come - after the person has arrived - there's no question of the person's not having come yet. One hears it from the hostess at many parties.
> 
> I'm not convinced, you see, that this is the conditional at all. It seems to me the simple past, like were able to.


 
In these cases it clearly isn't being used as a conditional, it is being used as simple past, which, as I pointed out in an earlier post, is common usage. I agree "I'm glad you could come/make it" is a common expression, and I notice that it goes against my suggested rule of only using _could _(past) for general abilities. However, there are many instances in which such a construction sounds strange to me, as in the sentence quoted from Wenger, and "I could study last weekend". Since I find many instances in which _was/were able to_ sounds much better in the past, I'd recommend non-natives to only use _could _for conditionals.


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## Ynez

According to my grammar book, all that you are saying about "general ability = could" and "particular situation = was able to" is perfect.

Then, my book also points out "could" is the most common with verbs like "understand", "see", "remember" and some others...

Also, "couldn't" (the negative form of could) is always possible.

When reading you all now, I can see my book is telling me the truth


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## cheshire

Ynez said:


> Then, my book also points out "could" is the most common with verbs like "understand", "see", "remember" and some others...


Would it be because those kinds of verbs are of involuntary nature rather than voluntary? What about "listen to"? Could we say "*I could listen to Bach's music that day.*"(meaning, "I was able to, and actually listened to it.")?



Thomas Tompion said:


> _
> 
> I've rather lost track who said the quote above, but Cheshire asked for it to be rewritten, so here goes.
> 
> It would never occur to me to use 'could' in this context because, putting it like that makes it appear that I might have been able to study, without specifying whether I actually did or didn't.
> 
> I'm not asking for any prizes for the style of the translation - I've deliberately spelled this out at some length, in the hope of being clear.
> 
> I don't actually agree with the sentence as an interpretation of 'could' in the sentence about the gas men, but that's as maybe._


_Thanks TT, you're angle in disguise!



liliput said:



			In these cases it clearly isn't being used as a conditional, it is being used as simple past, which, as I pointed out in an earlier post, is common usage. I agree "*I'm glad you could come/make it*" is a common expression, and I notice that it goes against my suggested rule of only using could (past) for general abilities. However, there are many instances in which such a construction sounds strange to me, as in the sentence quoted from Wenger, and "I could study last weekend". Since I find many instances in which was/were able to sounds much better in the past, I'd recommend non-natives to only use could for conditionals.
		
Click to expand...

I feel much previleged to be able to read this thread! It's so wealth of new information!
I'd think of the sentence this way: In "I'm glad that SV." or "I'm glad to INFINITIVE.", Neither "SV" nor "INVINITIVE"  call for past tense which is otherwise required. You never say (2), although it's in the past that "I" actually heard "that."
(1) I'm glad to *hear *that.
(2) * I'm glad to *have heard* that.​But you know, I'm not a native cat!_


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## liliput

I thought of another good example:
What if I ask the question; "Could the USA conquer Mexico?" If it's always OK to use could as the past tense, how do you know if I'm asking about a past ability (Was the USA able to conquer Mexico 150 years ago?) or a present possibility (Does the USA currently have the military capablility to conquer Mexico?).
Cortes was able to conquer Mexico.
The USA could conquer Mexico (if it wanted to).


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## Thomas Tompion

liliput said:


> I thought of another good example:
> What if I ask the question; "Could the USA conquer Mexico?" If it's always OK to use could as the past tense, how do you know if I'm asking about a past ability (Was the USA able to conquer Mexico 150 years ago?) or a present possibility (Does the USA currently have the military capablility to conquer Mexico?).
> Cortes was able to conquer Mexico.
> The USA could conquer Mexico (if it wanted to).


 
You can get round the ambiguity by making the conditional explicit with Would the USA be able to conquer Mexico? as opposed to Was the USA able to conquer Mexico, or would the USA have been able to conquer Mexico?

Wenger was saying: I'm glad we were able to win not I'm glad we would be able to win, which is meaningless. Didn't someone suggest he was using a conditional?


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## liliput

Thomas Tompion said:


> You can get round the ambiguity by making the conditional explicit with Would the USA be able to conquer Mexico? as opposed to Was the USA able to conquer Mexico, or would the USA have been able to conquer Mexico?
> 
> Wenger was saying: I'm glad we were able to win not I'm glad we would be able to win, which is meaningless. Didn't someone suggest he was using a conditional?


 
I argue that the conditional _could_ *is* explicit, it's necessary to make the past tense explicit by using "was/were able to", although of course "would be able to" is fine and is the same as "could".
I don't think anyone suggested that Wenger was using a conditional, clearly he was talking in past tense about the game that they had just won. It was suggested that his use of _could_ *sounds like* a conditional and therefore sounds odd in a non-conditional context.


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## Thomas Tompion

liliput said:


> I argue that the conditional _could_ *is* explicit, it's necessary to make the past tense explicit by using "was/were able to", although of course "would be able to" is fine and is the same as "could".
> I don't think anyone suggested that Wenger was using a conditional, clearly he was talking in past tense about the game that they had just won. It was suggested that his use of _could_ *sounds like* a conditional and therefore sounds odd in a non-conditional context.


 
I didn't understand your first paragraph, Liliput.  My worry is that I could can mean either I was able to or I would be able to.  That's what I meant about could not being explicitly conditional.

I didn't know if I could swim in the pool - I didn't know if I was able to swim in the pool or I didn't know if I would be able to swim in the pool.


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## liliput

Thomas Tompion said:


> I didn't understand your first paragraph, Liliput. My worry is that I could can mean either I was able to or I would be able to. That's what I meant about could not being explicitly conditional.
> 
> I didn't know if I could swim in the pool - I didn't know if I was able to swim in the pool or I didn't know if I would be able to swim in the pool.


 
My point was that, from my point of view, "Could the USA conquer Mexico?" can *only* mean "Would the USA be able to conquer Mexico?" so there is no need to use the alternative. If I wanted to talk about the past I would say "Was the USA able to...?" *never *"Could the USA...?"

"I didn't know if I could swim in the pool" I can't imagine when you would use this sentence rather than "I didn't know if I was allowed to swim in the pool" or "I didn't know if I would be allowed to...". If you used it, I would assume you meant "I didn't know if I'd be able too...". Unless you had amnesia, you would know if you were able to swim or not.


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## Thomas Tompion

liliput said:


> My point was that, from my point of view, "Could the USA conquer Mexico?" can *only* mean "Would the USA be able to conquer Mexico?" so there is no need to use the alternative. If I wanted to talk about the past I would say "Was the USA able to...?" *never *"Could the USA...?"
> 
> "I didn't know if I could swim in the pool" I can't imagine when you would use this sentence rather than "I didn't know if I was allowed to swim in the pool" or "I didn't know if I would be allowed to...". If you used it, I would assume you meant "I didn't know if I'd be able too...". Unless you had amnesia, you would know if you were able to swim or not.


 
Thank you for the reply.  I think we may just have to disagree.  I don't see why Could the USA conquer Mexico? can't mean Was the USA able to conquer Mexico?  Could is the past tense of can, as well as the conditional.  At what stage could Napoleon see that the Russian campaign was a disaster?  The question seems perfectly normal to me.

As for the swimming example: I didn't know if I could swim in the pool you allow to mean 'I didn't know if I'd be able to..', but not 'I didn't know if I was able to'.  Maybe I didn't know if I was allowed to swim (if I could swim) even though I was actually swimming.  I don't think amnesia comes into it, just lack of information, or supervision.  Maybe the attendant was asleep.


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## liliput

Thomas Tompion said:


> Thank you for the reply. I think we may just have to disagree. I don't see why Could the USA conquer Mexico? can't mean Was the USA able to conquer Mexico? Could is the past tense of can, as well as the conditional. At what stage could Napoleon see that the Russian campaign was a disaster? The question seems perfectly normal to me.
> 
> As for the swimming example: I didn't know if I could swim in the pool you allow to mean 'I didn't know if I'd be able to..', but not 'I didn't know if I was able to'. Maybe I didn't know if I was allowed to swim (if I could swim) even though I was actually swimming. I don't think amnesia comes into it, just lack of information, or supervision. Maybe the attendant was asleep.


 
There's no need to thank me, discussing such things helps me to clarify them for myself and to see alternative opinions.
I have to point out that the problems with ambiguity only arise from using _could _in all cases in the past. If we stick to the rule of using _could_ only for general abilities in the past and for conditionals, the ambiguity disappears.
This is why I only interpret your swimming pool sentence as a conditional (or a case of amnesia) - I wouldn't use _could _for a specific instance in the past.
I acknowledge that there may be certain exceptions, but since these exceptions work just as well, or better, with "was/were able to", the rule is a useful one.


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## Thomas Tompion

liliput said:


> There's no need to thank me, discussing such things helps me to clarify them for myself and to see alternative opinions.
> I have to point out that the problems with ambiguity only arise from using _could _in all cases in the past. If we stick to the rule of using _could_ only for general abilities in the past and for conditionals, the ambiguity disappears.
> This is why I only interpret your swimming pool sentence as a conditional (or a case of amnesia) - I wouldn't use _could _for a specific instance in the past.
> I acknowledge that there may be certain exceptions, but since these exceptions work just as well, or better, with "was/were able to", the rule is a useful one.


 
But you seem to acknowledge that other people use the word in that way, so isn't it dangerous to maintain that using could avoids ambiguity, on the grounds that you personally only use it with conditional rather than with simple past force?  It sounds a bit as though you are developing a private way of using the word.

You say 'if we stick to using it in a particular way' we avoid ambiguity, but, as we both know, ambiguities stem from established patterns of speech; even the French Academy hasn't managed to police the language at all effectively.

I'm not quite clear what you mean by 'general abilities in the past'?  Does Napoleon's ability to realize that the Russian campaign was a disaster a general ability, or a specific instance?


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## Ynez

chesire, the English grammar books we foreigners read mostly focus on describing "normal use", so there hasn't got to be a reason for some verbs being most commonly used with "could". If there is some reason, I don't know it 

And I don't know what to say about your example of "listen", sorry.

Thomas, your Napoleon's example uses the verb "see", which is supposed to be used normally with "could".

Typical examples of general ability in the past are:

I could play the piano when I was 6.
I could do that when I was....

Thomas, reading you, I am getting the feeling you don't think it would be a terrible mistake to use "could" when "was able to" is supposed to be used. Am I right?


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## liliput

Thomas Tompion said:


> But you seem to acknowledge that other people use the word in that way, so isn't it dangerous to maintain that using could avoids ambiguity, on the grounds that you personally only use it with conditional rather than with simple past force? It sounds a bit as though you are developing a private way of using the word.
> 
> You say 'if we stick to using it in a particular way' we avoid ambiguity, but, as we both know, ambiguities stem from established patterns of speech; even the French Academy hasn't managed to police the language at all effectively.
> 
> I'm not quite clear what you mean by 'general abilities in the past'? Does Napoleon's ability to realize that the Russian campaign was a disaster a general ability, or a specific instance?


 
If I use _could_ this way, then I avoid ambiguity in my sentences, which is a good thing. I imagine that most people would choose the least ambiguous  form for a particular sentence, unless they are deliberately trying to create ambiguity. Of course I can understand a sentence that uses _could _where I wouldn't normally use it, but it would look odd to me and I would regard it as a minor error. 
A general ability would be the ability to ride a horse, speak a language, play the guitar, etc. Your Napoleon sentence doesn't look bad to me, and I think the ability to see/understand something may be a kind of grey area between general ability and specific instance. I find it interesting that the grammar books that make the same claim as me apparently state specific verbs (such as _see_ and _understand_) which work well with _could_ in the past tense (see Ynez's posts).


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## Thomas Tompion

liliput said:


> If I use _could_ this way, then I avoid ambiguity in my sentences, which is a good thing. I imagine that most people would choose the least ambiguous form for a particular sentence, unless they are deliberately trying to create ambiguity. Of course I can understand a sentence that uses _could _where I wouldn't normally use it, but it would look odd to me and I would regard it as a minor error.


 
My point is that what seems to you unambiguous, because you have what I regard almost as a private sense about how could should be used, would actually be ambiguous, because other people don't all share your use.

I can't see how could which can mean (for many people) both the conditional (I would be able) and the simple past (I was able), can be less ambiguous that using I would be able, or I was able, to point the distinction.

  I think this is where we were two posts back.  I'm sure I'm missing something basic.


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## liliput

I think I may have the same grammar book as Ynez. 
Specifically, it states that _*could* _is *sometimes* the past tense of can. It's used especially with; *see, hear, smell, taste, feel, remember, understand*. 
*Could* is also used for *general ability *or* permission* (so perhaps the swimming pool example was good after all). 
Referring to what happened in a *particular situation*, we use _*was/were* *able to*_ or *managed to.*
Compare*:*
I was an excellent tennis player. I* could* beat anyone*.*
Jack played well, but I *was able to* beat him*.*

The negative *couldn't* is possible in all situations.


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## Thomas Tompion

Ynez said:


> Thomas, reading you, I am getting the feeling you don't think it would be a terrible mistake to use "could" when "was able to" is supposed to be used. Am I right?


 
Hi Ynez,  Well, you may be.  It depends obviously on what you mean by when 'was able to is supposed to be used.  The simplest thing might be to set out a few more examples, if the ones we've been using aren't suitable.  I don't think there are many cases where the two forms can't be interchanged. 

Could is open to another form of ambiguity to the one Liliput and I were talking about - it's often used to mean that you had permission.  I could fish in the pond can mean both I was able to fish in the pond (I had a rod and a reel and line and bait) and I was allowed to fish in the pond (my dad didn't mind and I had a licence).

And notice that Liliput doesn't agree with me.


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## Thomas Tompion

liliput said:


> I think I may have the same grammar book as Ynez.
> Specifically, it states that _*could* _is *sometimes* the past tense of can. It's used especially with; *see, hear, smell, taste, feel, remember, understand*.
> *Could* is also used for *general ability *or* permission* (so perhaps the swimming pool example was good after all).
> Referring to what happened in a *particular situation*, we use _*was/were* *able to*_ or *managed to.*
> Compare*:*
> I was an excellent tennis player. I* could* beat anyone*.*
> Jack played well, but I *was able to* beat him*.*
> 
> The negative *couldn't* is possible in all situations.


 
The examples are a great help.  You see I'd be quite happy to say:

I was an excellent tennis player.  I was able to beat anyone (I'd prefer could but was able wouldn't raise an eyebrow)

I find the second example much more persuasive than the first.

Jack played well, but I could beat him (here I would really want to say I was able - and if I wanted to use could I'd be tempted to say I found I could beat him): perhaps found is one of those verbs on Ynez's list.

So perhaps the book has a bit of a point.  It's very interesting, and far from being as clear-cut, to my mind, as the book suggests.


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## Ynez

I think the most compulsory use of "was able to" is when the idea is similar to "managed to", that is, you needed some effort to get it done.

I was trying to open the door but couldn't.
My neighbour came and, after a while, we were able to open it.

Do these sentences sound natural?


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## Thomas Tompion

Ynez said:


> I think the most compulsory use of "was able to" is when the idea is similar to "managed to", that is, you needed some effort to get it done.
> 
> I was trying to open the door but couldn't.
> My neighbour came and, after a while, we were able to open it.
> 
> Do these sentences sound natural?


 
Yes, they do, and I wouldn't say we could open it.  As in Liliput's example, I'd want to say we found we could open it.


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## Ynez

thank you


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## cheshire

liliput said:


> My point was that, from my point of view, *"Could the USA conquer Mexico?" can only mean "Would the USA be able to conquer Mexico?" *so there is no need to use the alternative. If I wanted to talk about the past I would say "Was the USA able to...?" *never *"Could the USA...?"
> 
> "I didn't know if I could swim in the pool" I can't imagine when you would use this sentence rather than "I didn't know if I was allowed to swim in the pool" or "I didn't know if I would be allowed to...". If you used it, I would assume you meant "I didn't know if I'd be able too...". Unless you had amnesia, you would know if you were able to swim or not.


Is the use of "could" for "general ability/availability/possibility in the past" an _*Americanism*_?


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## liliput

cheshire said:


> Is the use of "could" for "general ability/availability/possibility in the past" an _*Americanism*_?


 
A good question.
The grammar book that I looked in claims to deal with North American English grammar. However, the use of _could,_ as described in the book, fits with the usage that I as a BE speaker am familiar with. I have another book, also written by an American, which uses _could _in all cases in the past although it acknowledges that some grammarians may have other views.
So, the short answer is no, I don't think it's an Americanism.


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## liliput

Some more examples for my friend TT:

Could as past with particular verbs;
*When we went into the house, we could smell something burning.*

Could as past for general ability;
*My grandfather could speak ten languages.*

Could as past for permission;
*We were totally free. We could do whatever we wanted.*

A particular situation;
*They didn't want to come, but we were able to persuade them (or we managed to persuade them).*


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## Thomas Tompion

liliput said:


> Some more examples for my friend TT:
> 
> Could as past with particular verbs;
> *When we went into the house, we could smell something burning.* - Agreed - *we were able* wouldn't do.
> 
> Could as past for general ability;
> *My grandfather could speak ten languages. - *Here I'd be quite happy with *he was able**.*
> 
> Could as past for permission;
> *We were totally free. We could do whatever we wanted. - *Here I'd be quite happy with *we were able.*
> 
> A particular situation;
> *They didn't want to come, but we were able to persuade them (or we managed to persuade them). - *Agreed - *we could* wouldn't do.


 
I've put some reactions in your post, Liliput. Have we established a pattern? What are your own reactions as a BE speaker?


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## liliput

Thomas Tompion said:


> I've put some reactions in your post, Liliput. Have we established a pattern? What are your own reactions as a BE speaker?


 
Yes, this is exactly the way I use _could_ in the past.


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## dn88

> Could as past for general ability;
> 1)* My grandfather could speak ten languages. - *Here I'd be quite happy with *he was able**.*
> 
> Could as past for permission;
> 2)* We were totally free. We could do whatever we wanted. - *Here I'd be quite happy with *we were able.*


In *1)* both seem fine to me.

In *2)* I am strongly for "could", or at least I think that "could" would be used much more frequently in this case, no?

I'm just curious...


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## liliput

dn88 said:


> In *1)* both seem fine to me.
> 
> In *2)* I am strongly for "could", or at least I think that "could" would be used much more frequently in this case, no?
> 
> I'm just curious...


 
Yes, _could_ is preferable, but there's no problem with _were able to_.


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## dn88

liliput said:


> Yes, _could_ is preferable, but there's no problem with _were able to_.



Okay, I see... Thank you for the clarification.


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## Dmitry_86

sound shift said:


> I remember Arsène Wenger, manager of Arsenal FC, speaking to a reporter after his team had won a match. He said,
> _I'm glad we could win_.
> 
> What he said sounded wrong to me. I would have said,
> _I'm glad we won _or
> _I'm glad we were able to win._


 
A strange phrase, indeed. I agree that "could" suggests to one a possibility of Arsenal defeating their rival but since the result is (I am speaking in the present and therefore use "is") known the possibility equals 100 percent so we know the result for sure. "I am glad" said by Wenger leads to the conclusion that "be able to" should be (rather, should have been) used by Wenger.


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## Pitt

<<New question merged to avoid duplication - older discussion found by following the rule "Please search before posting a new question" - enter "could was able" in search box for others>>

Hello,

I'd like to know if both sentences are correct:  

_1 As a child I *was able to* play the piano.
2 As a child I *could* play the piano._

Thanks in advance!


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## Joseph A

Hello everyone,
Could you please tell me if either "was able to" or "could" correct in the following sentences?
1. The prisoner (*a*. was able to  *b*. could) escape and has not been found yet.
2. The prisoner (*a*. was able to    *b*. could) escape last night.
3. The prisoner (*a*. was able to    *b*. could) escape.
I think in #1 only "was able to" is correct and in #2 and 3 both "was able to" and "could" are okay.
PS. As far as I know, if the doer of the action managed or succeeded in doing the action, at that time "was able to" is correct. If we don't whether the doer managed or not, at that time both "could" and "was able to" are correct.
I'm not sure if my understanding of the subject is correct or not.


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## Cagey

I agree with the guidance that:  if the doer of the action managed or succeeded in doing the action, at that time "was able to" is correct. Thus, I agree that 'was able to' is correct in the first sentence:
1. The prisoner *was able to*  escape and has not been found yet.​For the same reason, I would use 'was able to' in sentence #2.  We are talking about last night, so probably we know whether or not the prisoner escaped.   
2. The prisoner *was able to* escape last night.​*Note*: If we don't know whether he escaped, abut we know that it was possible, we can say 'may have escaped / may have been able to escape.​2b. The prisoner *could have escaped* last night. We haven't checked to see whether he did.​
I agree that either might be used in sentence #3, depending on the context.


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## Joseph A

Cagey said:


> I agree with the guidance that:  if the doer of the action managed or succeeded in doing the action, at that time "was able to" is correct. Thus, I agree that 'was able to' is correct in the first sentence:
> 1. The prisoner *was able to*  escape and has not been found yet.​For the same reason, I would use 'was able to' in sentence #2.  We are talking about last night, so probably we know whether or not the prisoner escaped.
> 2. The prisoner *was able to* escape last night.​*Note*: If we don't know whether he escaped, abut we know that it was possible, we can say 'may have escaped / may have been able to escape.​2b. The prisoner *could have escaped* last night. We haven't checked to see whether he did.​
> I agree that either might be used in sentence #3, depending on the context.


Thanks a lot.


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