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I/
1. The girl who is sitting by Jack is Mary.
2. Can you understand the question which he asked you last time?
3. Is that the girl whom we saw on TV last night?
4. Jack London, who wrote "Iron heel", is a famous American writer.
5. Hanoi, which is the capital of Vietnam, hosted 22 nd Sea Games.
6. The bad which I sleep on has no mattress.
7. The girl whom Peter is talking to is Mary.
8. The woman whom I was looking at smiled.
II/
1. electricity
2. alternative
3. non-renewable
4. participants
5. cultural