1. Were they told how to do it? ( Introduce "should")

Ans. Were they told how should they do it?

2. You couldn't have seen me last week. (Begin: It...)

Ans. It couldnt be that you have seen me last week.

3. We had to break the trunk open. (Begin: The...)

Ans. The trunk had to be broke open.

4. If it escaped, suspicion would automatically fall upon them. (Begin: They....)

Ans. They would autmatically fall under suspicion if it escaped.

5. The door was the only point of exit. (Use: ............................... through.)

Ans. The door was the only way through.

6. Geeta was lucky that there wasnt a car coming.

(Begin: It...........)

Ans. It was lucky for Geeta that there wasnt a car coming.

7. Start now or you wont arrive in time. (Begin: You...........)

Ans. You wont arrive in time if you dont start now.

8. I often helped him, but he never succeeded. (Begin: In spite of............)

Ans. In spite of the fact that I helped him often, he never succeeded.

9. "When did you reach Mumbai, Sheila?" I asked.

Ans. I asked Sheila when did she reach Mumbai.

10. He owed his success to his father. (Begin: It was.............)

Ans. It was his father whom he owed his success.

11.Should he see you, he would be surprised. (Begin: were................)

Ans. "No ideas"

12. It was the last time he saw his wife. (Begin: Never.....)

Ans. Never again did he ever see wife.

Please correct my mistakes. Leave the ones which are already correct. Thanx in advance Emotion: smile
1) Were they told how they should do it?

2. It couldn't be last week that you saw me.

5. The only exit was through the door.

9. I asked Sheila when she had reached Mumbai.

10.It was his father to whom he owed his success. (although more natural to say 'It was his father that he owed his success to).

11.Were he to see you, he would be surprised.Should he see you, he would be surprised.

12 Never again did he see his wife.

Note that there are quite a few minor errors throughout - even in the ones I haven't shown - and particularly missing apostrophes.
Students: We have free audio pronunciation exercises.
Please help soon. I shall be very grateful!
Thanks a lot. Please point the wrong ones. Thanks very much!