1.I haven't heard from him_since_he went to America.
2.He won't be here_unless_he is invited.
3.He will not go to the cinema_because_he is very busy.
4.We found the key_where_she had left it.
5.We found the books two days_before_he had gone away.
6.We had no sooner got to the station_than_the train left.
7.He is explaining clearly_so that_they could understand.
8.Do not leave the room_until_yor have finished the test.
9.she sang_when_she went along.