Cấu trúc thì quá khứ đơn tobe :

` ( + ) ` : S + was / were + ...

`- ` Chủ ngữ là I / he / she / it + was + ...

` - `Chủ ngữ là You / we / they + were + ...

` ( - ) `: S + was / were + not + ....

`- ` Chủ ngữ là I / he / she / it + was + not +  ...

` - `Chủ ngữ là You / we / they + were + not + ...

` ( ? ) ` : Was / Were + S + ... ? 

` - ` Was + He / she / it + ... ?

` -` Were + you / we / they + ... ? 

` - ` Was not ` =` Wasn't , Were not ` = ` Weren't

` 2 ` :

` ( + ) ` : I was in London last month

` ( - ) ` : I wasn't in London last month

` ( ? ) ` : Were you in London last month ? ( Nếu trong câu phủ định / khẳng định chủ ngữ là I thì khi hỏi ta sẽ dùng You để hỏi ) 

`2`

`(+)` I was in London last month

`(-)` I wasn't in London last month

`(?)` Were you in London last month ? 

`-----------------`

`=>` Quá khứ đơn

`-` $Tobe$

`(+)` S + was/were + .......

`(-)` S + was/were + not + ......

`(?)` Was/Were + S + ......... ?

`-` $V$ 

`(+)` S + $Ved/V2$

`(-)` S + didn't + V

`(?)` Did + S + V ......?