This is the answer:

Ex1: verbform

1. bought

2. didn't collect

3. was/ wore

4. reading

5. go (hình như câu này bn ghi lộn đề rùi. Nó phải là How often does he go swimming mới đúng)

6. is watching

7. doesn't do

8. are playing

9. reading/ watching

10. clean

Ex2: rewrite

1. Be to remember to turn off the light before going out.

2. You should go to bed early.

3. What's the matter with him?

4. How much did your sister weigh last year?

5. How long is this river?

6. How high is this mountain?

Ex1:

1. bought

2. didn't collect

3. was/ wore

4. reading

5. does....go

6. is watching

7. doesn't do

8. are playing

9. reading/ watching

10. clean

Ex2:

1. Be to remember to turn off the light before going out.

2. You should go to bed early.

3. What's the matter with him?

4. How much did your sister weigh last year?

5. How long is this river?

6. How high is this mountain?