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1. These cakes were made for my birthday party by my mother.
2. Dinner can be cooked by myself.
3. I will be given a special present in the party by him.
A special present will be given to me in the party by him.
4. All these food and drinks are bought in the supermarket by Tam.
5. The teacher asks him if he was the best student at Math there.
6. The man asked me if he might help me.
7. Dung told me that she would help me with my homework.
8. The boy who is reading a book is Nam.
9. The toy truck which is recycled from drink cans is cheap.
10. It's not easy for me to arrange these flowers beautifully.
11. It's difficult for him to do the homework.