Solve this:
1) I was present when the work was being done.
2) He worked as per the instructions.
3) Come back before seven o' clock.
4) As soon as he was punished,he cried.
5) Is he worthy of your trust?
6) He promised that he will help me.
7) Only when he worked hard, he passed the exams.
8)The explanation given by them can't be true.