V

1. It is very đifficult to find a good job in the countryside. > Finding a good job in the countryside is very difficult.

2. It's the first time I have ever been to London. >I have never been to London before.

3. I studied very hard. I passed the exam easily. (so) -> I studied very hard, so I passed the exam easily.

4. I feel very sleepy now. I stayed up late to watch TV last night. => Because I stayed up late to watch TV last night, I feel very sleepy now.

5. When did you start to learn English? =>How long have you learnt English ?

VI:

1. to learn/to use

2. Have you written/have finished

3. was built

4. Did you use 

5. Collecting / won't continue

I/ 1. Finding a good job in the contryside is very difficult.

   2. I have never been to London.

   3. I study very well, so I passed the exam easily.

   4. Because I stayed up late to wacth TV at night, so I'm feeling sleepy now.

   5. How long have you learnt English?

II/ 1. It's necessary to learn how to use a computer.

2. Have you written your project report yet? - Yes, I have finished.

3. Our school was built five years ago.

4. Did you use to live in the contry when you was young?

5. Collecting stamps is Minh's favorite activity, but he says he won't continue this hobby in the future.