Ответ:

1. There is an apple tree near the playground.

a. Is there an apple tree near the playground?

b. What is there…near the playground?

2. They will be busy tomorrow because they will have a test soon.

a. Will they be busy... tomorrow?

b. Why  will…they  be busy... tomorrow?  

3. There will be a new bookshop near the stadium.

a. Will  there  be…a new bookshop... near the stadium?

b. Where …will there…be…a new bookshop?

4. That tree fell down yesterday.

a. Did that …tree fall down yesterday?

b. When did …that …tree fall down?

5. He became a doctor in 1981.

a. Did he …become a doctor in 1981?

b. Who became a doctor in 1981?

6. The lesson began two minutes ago.

a. Did the lesson begin… two minutes ago?

b. When did the lesson begin?

7. It snowed almost every day.

a. Did it snow almost every day?

b. How often did it snow?

8. He spends his holidays in the country.

a. Does he spend…his holidays in the country?

b. Where does he spend…his holidays?