1.Liz didn't buy many suovenirs in the HCM City.
Did Liz ​buy many suovenirs in the HCM City?

1.Liz bought many souvenirs in Ho Chi Minh City.
(-)Liz didn't buy many souvenirs in Ho Chi Minh City.
(?)Did Liz buy many souvenirs in Ho Chi Minh city?
2.I was very tired after the trip.
(-)I wasn't very tired after the trip.
(?)Were you very tired after the trip?
3.They are watching my father's new motorbike.
(-)They aren't watching my father's new motorbike.
(?)Are they watching your father's new motorbike?

1,
(-) Liz didn't buy many souvenirs in the HCM City.
(?) Did Liz buy many suovenirs in the HCM City?

2.
(-)I wasn't very tired after the trip.
(?)Were you very tired after the trip?

3,
(-)They aren't watching my father's new motorbike.
(?)Are they watching your father's new motorbike?