Ответ:
- 1) It had become cold before reached the destination.
- 2) We had won the tournament before the last round.
- 3) My friend had taken up playing baseball before he was 10.
- 4) The city had changed greatly by the 2000s.
- 5) The player had twisted his shoulder before the last volleyball game.
- 6) Mary had lost her handbag before she left the shop.
- 7) By the end of the month, the earthquake had ruined the city.
- 8) The students had finished writing their papers before the lesson was over.
- 9) I had understood everything before she told me about the problem.
- 10) George had learnt to play the guitar before he joined the band.
Краткое пояснение:
Краткое пояснение: Необходимо раскрыть скобки, поставив глагол в форму Past Perfect. Past Perfect образуется при помощи вспомогательного глагола had и третьей формы основного глагола.