I/
1. D
2. A
3. B
4. C
5. B
6. C
II/
1. bought (quá khứ đơn)
2. goes (hiện tại đơn)
3. will go (tương lai đơn)
4. Have they studied (thì hiện tại hoàn thành)
III/
1. Because the news is boring, I don't watch it.
2. If we don't protect the environment, we will destroy ourselves.
3. Trung is the tallest person in the group.
4. There is a living room, a bedroom and a kitchen in my house.