Exercise 6:

1. My teacher told me to look up the new words.
2. The Sky train is packed with commuters at rush hour.

Exercise 7:

1. He goes to school everyday.
2. She doesn't do her homework every day.
3. Lan went to school by bike last week.
4. She is a student.
5. He was at home yesterday.
6. She has lived here for 3 years.
7. Lan is watching TV now.
8. He is going to HN tomorrow.
9. I play badminton every afternoon.
10. She didn't buy a new house yesterday.
11. She was in Lao Cai last week.
12. I bought a new shirt this morning.
13. Ba watched TV last night. Did you write a letter two days ago?
14. What did you buy yesterday?