1)to return; 2) has not been returned; 3) returns; 4)with; 5) is returned; 6) should return; 7) has returned; 8) returning; 9) is returning; 10) for
1. The doctor recommended that i ...home as soon as hot weather set in.
2. I’m afraid , the book you are looking for ... to the library yet. Someone must still keeping it .
3. On ... to the office the staff continued discussing the terms.
4. Jim is not a reliable person. He hardly ever... things on time.
5. What went wrong ... that gold watch you used to have?

1.6) should return;   2. 2) has not been returned   3.8) returning;

4. 3) returns; 5.4)with;

Объяснение:

1. The doctor recommended that i should return home as soon as hot weather set in.  Доктор порекомендовал мне вернуться домой, как только начнется жаркая погода.

2. I’m afraid , the book you are looking for has not been returned to the library yet. Someone must still keeping it . Боюсь, книга, которую вы ищете, еще не возвращена в библиотеку. Кто-то  все еще держит ее у себя.

3. On returning  to the office the staff continued discussing the terms.

По возвращении в офис сотрудники продолжали обсуждать условия.

4. Jim is not a reliable person. He hardly ever returns things on time.

Джим не надежный человек. Он почти никогда не возвращает вещи

вовремя.

5. What went wrong with that gold watch you used to have? Что случилось  с теми золотыми часами, которые у тебя были?