1.The nurse taught Hoa how to give first-aid on the phone.

⇒Hoa was taught how to give first-aid on thephone by the nurse.
2. He prefers English to Literature.

⇒ He is like English more than Literature.

3. Thinking of making toys from used paper was his interesting idea.

⇒His interesting that he thought of making toys from used paper.

4. Peter saved 10£ a month, so that he could go on holiday in the summer.

⇒Because Peter saved 10£ a month, he could go on holiday in the summer.

5. Has everyone left the room?

⇒Everyone has left the room, hasn't they?

6. “ You broke my window glass this morning, Tom” said Tom’s neighbor.

⇒Tom’s neighbor said that he had broken his/her window glass that morning.

7. Your book is 15,000 dong. My book is 30,000 dong.

⇒ Your book and my book are 15,000 and 30,000 dong.

8. What do you say in the situation you want your friend tidy the class room?

⇒ How did you said in the situationed you want your friend tidy the class room?

9. I couldn’t do the test because it was very hard.

⇒I could not do the test because it was very hard.

10. Lan told me not to play with matches because it was dangerous.

⇒Lan said me not to play with matches because it was dangerous.