Questions & Answers about В августе море тёплое, и на пляже много людей.
Because after в when it means in a time period, Russian normally uses the prepositional case.
- август = August
- в августе = in August
This is a very common pattern:
- в январе = in January
- в мае = in May
- в году = in the year
So в августе means in August.
Because море is a neuter noun, and adjectives in Russian must agree with the noun in gender, number, and case.
- море = sea, and it is neuter
- neuter singular adjective form of тёплый is тёплое
So:
- тёплый = masculine
- тёплая = feminine
- тёплое = neuter
- тёплые = plural
That is why море тёплое means the sea is warm.