I :

1. Thinking of making toys from used paper was he's interesting idea 

-> It is interesting that he thought of making toys from used paper

2. He wasn't come back to his home village for over 20 years

-> It's over 20 years since he last came back to his home village

3. That's the strangest film I've ever seen 

-> I have never seen such a strange film before

4. The last time we met each other was ten years ago.

-> We haven't met each other for ten years

5. Mai said " it is raining heavily outside."

-> Mai said " That was raining heavily outside. "

6. Have you ever played a compter game before ?

->Did you play a compter game ?

7. France presented the statue of Liberty to the United States in 1876.

-> The statue of Liberty was presented  to the United States in 1876 by France

8.The water was so cold that the children couldn't swim in it

->The water wasn't warm enough for the children to swim in 

9.People should stop experiments on animals

-> Experiments on animals should be stopped

10. Ann said to me "will you do English test tomorow?"

->Ann asked me if I would do english test the following day.

II :

1. I / not / see / him / since / we / leave / school.

I haven't seen him since we left school.

2. this / be / firs time / tim / see / rice paddies

This is the first time I have seent he rice paddies.

3. compost / make / from / household and garden waste

Compose is made from household and garden waste.

4. he/tell/me/that he/borrow/book/ schooll library.

He told me that he borrowed books from school library.

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