Bài 1.
(+) I did my homework last night.
(+) I swam in the sea last summer.
(+) She lived in Viet Nam last year.
(+) He didn't go to the cinema yesterday.
(-) We didn't ride our bike yesterday.
(-) They didn't have breakfast yesterday.
(?) Did they complete their homework last night ?
(?) Did you go to the supermarket last month ?
(?)Did she learn her homework yesterday ?
(?) Did he wear his coat yesterday ?