Question

1. "What time does the play begin?" He said
=> He wanted to know
2. It's two years since John wrote to me.
=> John hasn't  
3. Stop smoking in this room. (allow)
=> We 
4. You don't study hard, you don't get good grades.
=> If you want

Answer 1

1. "What time does the play begin?" He said
=> He wanted to know what time the play begun
2. It's two years since John wrote to me.
=> John hasn't written to me for 2 years
3. Stop smoking in this room. (allow)
=> We don't allow smoking in this room
4. You don't study hard, you don't get good grades.
=> If you want to get good grades, you should study hard

Answer 2

1. => He wanted to know what time the play begun

2. => John hasn't written to me for 2 years

3. => We don't allow smoking in this room

4. => If you want to get good grades, you should study hard