Ukrainian/Grammar

Irregular (athematic) verbs
However, there are only four "truly" irregular verbs. They originate from an archaic conjugation (called "athematic") and their inflection cannot be traced from general rules. Those verbs are: бути (English be), дати (Eng give), їсти (Eng eat) and доповісти. Regular verb conjugation

The Numbers (1 to 10)
Here are the Ukrainian numbers from one to ten.
 * 1) один  one
 * 2) два two
 * 3) три  three
 * 4) чотири  four
 * 5) п'ять  five
 * 6) шість six
 * 7) сім seven
 * 8) вісім eight
 * 9) дев'ять nine
 * 10) десять  ten

Declension
The word один is deflected by gender and number as an adjective.

один рік one year

одне вікно one window

одна ву́лиця one street

одні две́рі one door

The plural form одні is used with nouns that have no singular form and are used in plural even when denoting a single object. It also can be used when один means alone or only.