CÔNG THỨC THÌ QUÁ KHỨ ĐƠN ĐỐI VỚI ĐỘNG TỪ THƯỜNG:

(+) S+V2/ED 

(-) S+DIDN'T+V0

(?) DID+S+V0?

CÔNG THỨC THÌ QUÁ KHỨ ĐƠN ĐỐI VỚI ĐỘNG TỪ TOBE:

(+) S+WAS/WERE

(-) S+WASN'T/WEREN'T

(?) WAS/WERE+S..?

A) Dấu hiệu nhận biết: yesterday -> chia thì QKĐ

1 - My sister tidied her room yesterday. (+)

2- My sister didn't tidy her room yesterday. (-)

3- Did your sister tidy her room yesterday? (?)

B) Dấu hiệu nhận biết: last summer -> chia thì QKĐ

1- We lived in London last summer. (+)

2- We didn't live in London last summer. (-)

3- Did you live in London last summer? (?)

C) Dấu hiệu nhận biết: last night -> chia thì QKĐ

1- Sandra and Elsa talked on the phone last night. (+)

2- Sandra and Elsa didn't talk on the phone last night. (-)

3- Did Sandra and Elsa talk on the phone last night? (?)

$@dream$

`A)` 1- tidied

       2 - didn't tidy

       3 - Did - tidy

`B)` 1- lived

      2 - didn't live

      3 - Did - live

`C)` 1 - talk

       2 - didn't talk

       3 - Did - talk

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Thì quá khứ đơn:

$(+)$ S + Ved/ V2.

$(-)$ S + didn't + Vo.

$(?)$ Did + S + Vo?