Đáp án:

$3.$ Lan saw you in the park last week.

$→$ Lan didn't see you in the park last week.

$→$ Did Lan see you in the park last week?

$4.$ We were in the countryside last summer.

$→$ We didn't be in the countryside last summer.

$→$ Did we be in the countryside last summer?

$5.$ Mrs. Robinson bought a poster.

$→$ Mrs. Robinson didn't buy a poster.

$→$ Did Mrs. Robinson buy a poster?

$6.$ Liz enjoyed her vacation in Da Lat last year.

$→$ Liz didn't enjoy her vacation in Da Lat last year.

$→$ Did Liz enjoy her vacation in Da Lat last year?

$7.$ Her aunt gave her a new skirt.

$→$ Her aunt didn't give her a new skirt.

$→$ Did her aunt give her a new skirt?
$8.$ He was in our class two hours ago.

$→$ He didn't be in our class two hours ago.

$→$ Did he be in our class two hours ago?

$9.$ They watched a good footballmatch on TV last night.

$(-)$ They didn't watch a good footballmatch on TV last night.

$(?)$ Did they watch a good footballmatch on TV last night?

10. Peter sent that letter to Marry yesterday morning.

$(-)$ Peter didn't send that letter to Marry yesterday morning.

$(?)$ Did Peter send that letter to Marry yesterday morning?

11. Jane's mother bought a new car last month.

$(-)$ Jane's mother didn't buy a new car last month.

$(?)$ Did Jane's mother buy a new car last month?

12. We visited Halong Bay three years ago.

$(-)$ We didn't visit Halong Bay three years ago.

$(?)$ Did we visit Halong Bay three years ago?

13. They left for Hai Phong in 1999.

$(-)$ They didn't leave for Hai Phong in 1999.

$(?)$ Did they leave for Hai Phong in 1999?

14. They built a new school in my village ten month ago.

$(-)$ They didn't build a new school in my village ten month ago.

$(?)$ Did they build a new school in my village ten month ago?

15. I borrowed a lot of book in the library last weekend.

$(-)$ I didn't borrow a lot of book in the library last weekend.

$(?)$ Did I borrow a lot of book in the library last weekend?

$----------------------$

* Giải thích:

Công thức thì quá khứ đơn:

$\text{(+) $S$ + $be$ / $V_e$$_d$ + ..... ($be$ : $was$/ $were$)}$

$\text{($-$) $S$ + $did$ + $not$ + $V$ + ....}$

$\text{($?$) $Did$ + $S$ + $V$ + ....?}$

$----------------------$

$@nguyendiepphuong59391$

Công thức thì QKĐ (V: to be)

(+) S + was/were + ... 

(-) S + was/were + not ... 

(?) Was/Were + S ... ? 

S số ít, I, he, she, it + was

S số nhiều, you, we ,they + were

Công thức thì QKĐ (V: thường)

(+) S + V2/ed 

(-) S + didn't + V1 

(?) Did + S+ V1?

DHNB: ago, last (year, month ...), yesterday, in + năm QK, ...

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3.

- Lan didn't see you in the park last week.

- Did Lan see you in the park last week?

4.

- We weren't in the countryside last summer.

- Were you in the countryside last summer?

5.

- Mrs. Robinson didn't buy a poster.

- Did Mrs. Robinson buy a poster?

6.

- Liz didn't enjoy her vacation in Da Lat last week.

- Did Liz enjoy her vacation in Da Lat last week?

7.

- Her aunt didn't give her a new skirt.

- Did her aunt give her a new skirt?

8.

- He wasn't in our class two hours ago.

- Was he in our class two hours ago?

9.

- They didn't watch a good football match on TV last night.

- Did they watch a good football match on TV last night?

10.

- Peter didn't send that letter to Mary yesterday morning.

- Did Peter send that letter to Mary yesterday morning?

11.

- Jane's mother didn't buy a new car last month.

- Did Jane's mother buy a new car last month?

12.

- We didn't visit HalongBay three years ago.

- Did you visit HalongBay three years ago?

13. 

- They didn't leave for Hai Phong in 1999.

- Did they leave for Hai Phong in 1999?

14.

- They didn't build a new school in my village ten months ago.

- Did they build a new school in your village ten months ago?

15.

- I didn't borrow a lot of books in the library last weekend.

- Did you borrow a lot of books in the library last weekend?

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