1.

(-) He didn't write a book.

(?) Did he write a book?

2.

(-) She wasn't my boss.

(?) Was she your boss?

3.

(+) They build a new house.

(?) Did they build a new house?

4.

(+) I wasn’t at the concert last Sunday.

(?) Were you at the concert last Sunday?

5.

(+) I bought clothes in this little shop.

(-) I didn't buy clothes in this little shop.

6. 

(+) They were born in Korea.

(-) They weren't born in Korea.

7.

(-) We didn't swim in the lake.

(?) Did you swim in the lake?

8.

(-) We weren't at the gym last week.

(?) Were you at the gym last week?

9.

(+) She went to her office by car.

(?) Did she go to her office by car.

10.

(+) He was a good boy.

(?) Was he a good boy?

(-) mượn trợ động từ did; động từ tobe thêm not

(?) đưa did lên đầu đối vs đầu từ thường; còn động từ tobe đưa lên đầu như Was or Were