Помогите с английским плизз)

1. He (to break) a window yesterday.
2. I (to bring) a letter before she (to call).
3. Mary (to watch) TV while they (to cook) supper.
4. My mum (to come) home by 6 yesterday. 5. You (to open) the window when you (to return) yesterday.
6. The students (to prepare) for the exam from 3 to 7 last Monday.
7. They (to study) in London for 4 years.
8. After 1 (to see) her 1 (to remember) that we (to meet) many years before.
9. Nick (to visit) the USA after he (to Icarn) English.
10. They (to wait) for us all day long yesterday.
11. Peter (to go) to school since 2000.
12. The day before yesterday we (to write) a composition.

1. broke 2 had brought\called3.was watching\were cooking4had come 5 opened\had returned6 were preparing for7 have been studing 8 had seenemembered\had met( насчет этого не уверена)9 visited\ had learnt10 were waiting 11has been going to school 12 wrote