1.
a.Form
V to be
(+)S+V-ed/V2. You,we,they+were .
I,he,she,it+was.
(-)S+didn't+V-inf. You,we,they+were+not.
I,he,she,it+was+not.
(?)Did+S+V-inf? Were+you,we,they+...?
Was+I,he,she,it+...?
b.Use:
-Diễn tả thói quen trong quá khứ.
-Diễn tả sự việc đã kết thúc trong quá khứ.
c.adv:often,usually,yesterday,last...,...ago,in+mốc năm trong qk,when+MĐ qkđ.
2.
1.(-)It wasn't cloudy yesterday.
(?)Was it cloudy yesterday?
2.(-)In 1990 they didn't move to another city.
(?)Did they move to another city in 1990?