`-` When + S + Ved / V2 , S + was / were + V-ing

`-` While + S + was / were + V-ing , S + Ved / V2

`=>` Dùng để diễn tả hành động đang xảy ra , hành động chỉ xảy ra `1` lúc

`-` While + S + was / were + V-ing , S + was / were + V-ing

`=>` Dùng để diễn tả `2` hành động đang xảy ra cùng `1` lúc

`-` Thì QKĐ :

`+` KĐ : S + Ved / V2

`+` PĐ : S + didn't + V

`+` NV : Did + S + V ?

`=>` `DHNB` : ago , last , yesterday , in + Mốc thời gian trong Quá khứ , ...

`-` Thì QKTD :

`+` KĐ : S + was / were + V-ing

`+` PĐ : S + wasn't / weren't + V-ing

`+` NV : Was / Were + S + V-ing ?

`=>` `DHNB` : at this time yesterday , this time yesterday , ...

`*` I , He , She , It `+` was

`*` You , We , They `+` were 

`1`.switched off

`2`.were having

`3`.arrived

`4`.was watering

`5`.cried

`6`.was playing

`7`.Were you working ?

`8`.rang

`\text{# TF}`

Đáp án + Giải thích bước giải:

`1.` switched off

`2.` were having

`3.` arrived

`4.` was watering

`5.` cried

`6.` was playing

`7.` Were you working ?

`8.` rang

`(@)` Diễn tả 1 hành động đang xảy ra thì có 1 hành động khác xem vào:

`+` When + QKĐ + QKTD

`+` While + QKTD + QKĐ

`@` Thì QKĐ:

`(+)` S + V2/ed

`(-)` S + did not + Vo

`(+)` Did + S + Vo?

`@` Thì QKTD:

`(+)` S + was/were + V-ing

`(-)` S + was/were + not + V-ing

`(+)` Was/Were + S + V-ing?