When you make an appointment for a particular month or an event, use the preposition на/for. The month name remains grammatically unchanged. Когда? На какой месяц? / When? For what month?
- на январь – for January;
- на февраль – for February;
- на март – for March;
- на апрель – for April;
- на май – for May;
- на июнь – for June;
- на июль – for July;
- на август – for August;
- на сентябрь – for September;
- на октябрь – for October;
- на ноябрь – for November;
- на декабрь – for December.
Когда у вас запланирована свадьба? — На август. — When is your wedding planned? — For August.
To memorise the months names in Russian more quickly, you can set yourself up in the Russian calendar app. By paying regular attention to the Russian names, you will soon be able to recognise them in speech and use them yourself.