1.

(-) Liz didn't buy any souvenirs in ho Chi Minh city.

(?) Did Liz buy any souvenirs in ho Chi Minh city?

2.

(-) I wasn't very tired after the trip.

(?) Were you tired after the trip?

3. 

(-) They aren't watching my father's new motorbike.

(?) Are They watching my father's new motorbike?

4. 

(-) We didn't visit Cham Temples last month.

(?) Did you visit Cham Temples last month?

5.

(-) Trung's brother doesn't go on holiday in Ha Long Bay every summer.

(?) Does Trung's brother go on holiday in Ha Long Bay every summer?

6. 

(-) They will not take their son to the zoo next weekend.

(?) Will They take their son to the zoo next weekend?

7. 

(-) My parents don't live in the coutryside.

(?) Do your parents live in the coutryside?

8. 

(-) Tom didn't give me any American stamps five days ago.

(?) Did Tom give you any American stamps five days ago?

9. 

(-) Mrs.Oanh isn't our new literature teacher.

(?) Is Mrs.Oanh our new literature teacher?

10. 

(-) There wasn't a toy store next to the museum.

(?) Were there any toy stores next to the museum?