Dates, months, and years
Dates, months, and years: how to use cardinal and ordinal numerals to answer the questions What is the date today? On what date? In which year?
The months of the year are written with a small initial letter. They are all masculine.
январь - January
февраль - February
март - March
апрель - April
май - May
июнь - June
июль - July
август - August
сентябрь - September
октябрь - October
ноябрь - November
декабрь - December
To answer the question Какое сегодня число? (What is the date today?), the neuter form of the ordinal numeral is used (to agree with число, date) followed by the genitive case of the month: Сегодня первое мая. Today it is the 1st of May.
Note that in the case of compound numerals, only the last digit is in the ordinal form: Сегодня двадцать седьмое февраля. Todаy it is the 27th of Februаry.
To answer the question Какого числа? (On which date?), the ordinal numeral must be put into the genitive case: День рождения моего мужа третьего октября. My husband's birthday is on the 3rd of October.
To answer the question Какой год? (Which year?), Russian uses the following formula: 1999 = the one thousand nine hundred and ninety-ninth year
(одна) тысяча девятьсот девяносто девятый год = 1999 г.
i.e. the last digit is an ordinal numeral.
2000 = thе 2000 year = двухтысячный год = 2000 г.
2001 = thе two thousand and first year = две тысячи первый год = 2001 г.
2012 = две тысячи двенадцатый год = 2012 г.
Note that the letter г. (for год) usually follows the year when it is written in figures.
To answer the question В каком году? (Оn which year?), the ordinal numeral must be put into the prepositional case: В тысяча девятьсот пятьдесят третьем году. In 1953.
If details of dates and months are given before the year, then the ordinal numeral must be put into the genitive case: Она родилась тридцать первого марта тысяча девятьсот четырнадцатого года. She was born on 31st March 1914.
Source: onlinerussianlanguageschool.blogspot.com