Ex 10 :
1. He is the most wonderful person I have ever met.
2. He found a watch in the street, and then he tried to return it to the loser.
3. Have you received any letters from your brother lately?
4. My dad stopped smoking two years ago.
5. They have been in our country since January 1st, 2018.
6. I broke my car’s rear mirror recently.
7. My younger sister has just come back from Ho Chi Minh City.
8. Tim: Have you ever been to Da Lat, Peter?
- Peter: Yes, I came there two months ago.
9. I haven't seen John for a long time. The last time I saw him was 3 years ago.
10. He is very thirsty. He hasn't drunk since this morning.
Ex 11: 
1. After Ngoc Mai finishes her degree, she intends to work in her father’s company.
2. As you don't use your laptop at the moment, can I borrow it?
3. When she saw a snake at her feet, she screamed.
4. I finish the new Harry Potter book now, so you can borrow my copy if you like.
5. I was sure that I had met him before.
6. An old lady waved to stop us while we drove down the gravel road.
7. The film had already begun by the time we got to the cinema.
8. No matter what happens next I will help you.