Ответ:
Время указываем с at, месяцы и времена года — с in, дни недели — с on. Устойчивое выражение: at the weekend.
- She gets up at 7 o’clock.
- My mum’s birthday is in July.
- We go to the sea in summer.
- Ann goes to music lesson on Fridays.
- I visited my granny at the weekend.
