1.
(-) He didn't sent letters to his parents.
(?) Did he send letters to his parents?
2.
(-) My brother didn't spend his summer holiday on the farm.
(?) Did your brother spend his summer holiday on the farm?
3.
(-) The people weren't friendly
(?) Were the people friendly?
4
(-) Liz didn't enjoy her summer vacation last year.
(?) Did Liz enjoy her summer vacation last year?
5.
(-) Nam wasn't asbent from school yesterday.
(?) Was Nam absent from school yesterday?
Chúc bạn học tốt!! ^^