C

1

1 could

2 came

3 play

4 will buy

5 in

6 learning

7 is grown

2

1 for -> since

2 do you -> did you 

3 watching -> watch

4 will -> would 

D

1 She asked me if I liked go with her the next day.

2 This house was built 5 years ago.

4 He was busy so he didn't go to the party.

5 We wish we could speak English well.

1 She wishes she knew many english words.

2 I wish I could do these exercises.

1.

1. could

2. came

3. play

4. will buy

5. since

6. isn't

7. learning

8. is grown

2.

1. for - since

2. do - did

3. watching - watch

4. will - would 

D.

1. if I liked go with her the following day

2. was built 5 years ago

4. so he didn't go to the party 

5. could speak English well

2. I could do this exercise