`C`ấu trúc chung :

`-` QKĐ :

`+` KĐ : S + Ved / V2 `-` S + was / were + adj / n

`+` PĐ : S + didn't + V `-` S + wasn't / weren't + adj / n

`+` NV : Did + S + V `?` `-` Was / Were + S + adj / n `?`

`=>` `DHNB` : yesterday , ago , last , ...

`-` 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 , ...

`1`.broke

`2`.wasn't watching

`3`.heard / was doing

`\rightarrow` 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 ( `3 , 8` )

`4`.did ... get ?

`5`.were ... doing ?

`6`.was preparing / were doing

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

`=>` Dùng để chỉ về `2` hành động đang diễn ra cùng lúc

`7`.watered

`8`.was having / knocked

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

`9`.went

`10`.did ... get ?

`11`.was studying / was playing

`12`.visited

`13`.didn't do / was

`14`.weren't skating

`15`.phoned / didn't answer

`\text{# TF}`