# express number



## Odriski

Hi, I hear that in Czech there are 2 ways to express number? eg. 28, in Czech we can say "dvacet osm" or "osmadvacet", right? If so, what is the grammatical rule of the expression for the latter, like "osmadvacet"?

Many thanks


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## Hrdlodus

It is true.
it's for 21 – 99.

Jeden*a*_dvacet_ or jedn*a*_dvacet_
dva*a*_dvacet_
tři*a*_dvacet_
čtyři*a*_dvacet_
pět*a*_dvacet_
šest*a*_dvacet_
sedm*a*_dvacet_ (spelling: se-dm-*a*-_dva-cet_ or sed-m*a*-_dva-cet_)
osm*a*_dvacet_ (spelling: o-sm-*a*-_dva-cet_ or os-m*a*-_dva-cet_)
devět*a*_dvacet_

The same way for -_třicet_, -_čtyřicet_, ... , -_devadesát_.

As you know, this form is one-word. That form "_dvacet_ osm" separates the words.
Germans use this one-word form. (acht-*und*-_zwanzig_).

What about ordinals: 28. (28st)?
dvacátý osmý (dvacátá osmá etc.)
osmadvacátý (osmadvacátá atc.)

What about declesion?
with 28 men
s dvaceti osmi muži
s osmadvaceti muži


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## bibax

There is no special grammatical rule.

The addition of numbers is commutative, since x + y = y + x.
For example 20 + 8 = 8 + 20, since both expressions equal 28.

We read:
*dvacet a osm* _se rovná (= is equal to)_ *osm a dvacet

*Both expressions (in the decimal system) express the abstract quantity 28.

Rule 1. If we read a number in descending order the conjunction "a" is omitted in most cases:

3928 = 3000+900+20+8: tři tisíce [a] devět set [a] dvacet [a] osm

but usually 1001 = 1000+1 (nights): tisíc *a* jedna (noc)
 (tisíc jeden/jedna/jedno is also possible)

Rule 2. If we read a number in ascending order the conjunction is not omitted, however it is applicable only for the range 21-99:

28 = 8+20: osm *a* dvacet
99 = 9+90: devět *a* devadesát

Rule 3. The expressions like osm a dvacet are considered as one word.

Thus only the last numeral is declinable:

s osmadvacet*i* studenty (with 28 students), but s dvacet*i* osm*i* studenty;


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## Odriski

Thank you so much for your explanation


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## ilocas2

People say the reversed forms rarely.


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