1。The key……（lose），the boy cound‘t enter his house。
2。Do you remember……（I，return）the books to the library？
3。I saw the man……（knok）down and the driver……（dive）away。
4。He was head……（say）that she disagreed with him
5。Be quick！They are having the car……（wait）for us at the gate。

1。The key(lost)，the boy cound‘t enter his house。
2。Do you remember (my/me returning)the books to the library？
3。I saw the man (knocked) down and the driver (drive) away。
4。He was head (saying) that she disagreed with him(这句我不懂）
5。Be quick！They are having the car (waiting)for us at the gate。