Раскройте скобки в Past Simple или Past Perfect

1)Nick (return) from office by seven o'clock
2)We (to get) to the stadium at four o'clock but the game already (to start)
3)She (to come) at six o'clock.
4)I (to think) that my parents already (to return)
5)He (to be sure) that we (not to recognise) him.
6)You (to find) your key which you (to lose) before
7)Meg (to say) that she (to be) in this city
8) The doctor (to arrive) when we already (to help) him

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