=>

4. We haven't had a vacation since last year.  
5. This printer is under guarantee.
6. Our volunteering in communities makes a difference.
7. Have you finish your homework yet?
8. It's easy to get flu.

III/
1. The photograph is not as big as the painting.
2. The film we saw last week is not as interesting as this one.
3. The journey was not as long as we thought at first. 
4. Tim is the same age as Hoa.
5. She speaks English as well as her sister. 
6. Giang can't paint as well as Khanh.
7. Her book is different from mine.

IV/
1. I was sick, so I didn't go to school.
2. His hobby is interested in playing computer games in his free time.
3. His hobby is playing computer games in his free time.
4. I enjoy watching TV in the evening. 
5. I find learning English important.
6. The tickets to the show cost 
7. A lot of children are attracted by Charles Dickens' novels.
8. It only taks half an hour to get to the art gallery.
9. Your house is not as big as my house. 
10. The red car is more expensive than the black car.

11. The play is more interesting than this film.
12. Her book is different from mine.