Say what you were doing. Use the past continuous. Example: at 7 o'clock last night — I was watching TV at 7 o'clock.

1 I was doing homework at 5 p.m. yesterday (Я делал домашнее задание вчера в пять часов вечера).
2 I was talking to my mother on the phone two hours ago (Два часа назад я говорил с мамой по телефону).
3 I was playing football at 11 a.m. last Sunday (В одиннадцать дня в прошлое воскресенье я играл в футбол).
4 I was sleeping at 9.00 p.m. the day before yesterday (Позавчера в девять вечера я спал).
5 I was going to school an hour ago (Час назад я шел в школу).