=>
1. (-) My father didn't decorate the Christmas tree.
(?) Did your father decorate the Christmas tree?
2. (-) She didn't buy a new dress yesterday.
(?) Did she buy a new dress yesterday?
3. (-) They weren't late for school.
(?) Were they late for school?
4. (-) Mr Tam didn't take his children to the museum last Sunday.
(?) Did Mr Tam take his children to the museum last Sunday?
5. (-) Hoa didn't make a cushion for her armchair.
(?) Did Hoa make a cushion for her armchair?
6. (-) They didn't paint their house yellow.
(?) Did they paint their house yellow?
7. (-) This dress wasn't fit.
(?) Was this dress fit?
8. (-) I didn't see her two days ago.
(?) Did you see her two days ago?
Thì QKĐ
Đối với tobe :
(+) S was/were...
(-) S was/were not...
(?) Was/Were S...?
Đối với động từ thường :
(+) S V2/ed
(-) S didn't V
(?) Did S V?