Đáp án + Giải thích các bước giải:

`1.` was not/ wasn't 

`2.` were not/ weren't

`3.` left

`4.` was

`5.` told

`6.` didn't have

`7.` didn't know

`8.` bought

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Form:

`**` Tobe

(+) S + was/were + (a/an) + adj/n.

(-) S + was/were + not + (a/an) + adj/n.

(?) Was/were + S + (a/an) + adj/n? - Yes, S + was/were

                                                         - No, S + was/were + not

`**` Verb

(+) S + $V_{ed/c2}$ + O.

(-) S + didn't + V-inf + O.

(?) Did + S + V-inf +O? - Yes, S + did

                                      - No, S + didn't