`\color{#145277}{N}\color{#246483}{a}\color{#34768F} {e}\color{#44889B}{u}\color{#539AA7}{n}`

`@` For `+` quãng thời gian : trong khoảng (for a month, for a long time)

`@` Since `+` mốc thời gian : từ khi (since `2006`, since `2008`) / Since + V2

`bb\1.` S + started / began + V_ing / to – V + O + (time)

`->` S + have / has + V3 / ed +  O + since / for + time

`bb\2.` This is the first time + S + have / has + V3 / ed + O

`->` S + have / has + never + V3 / ed + O + before

`bb\3.` When did + S + V_bare + O `?`

`->` How long ago + did + S + V_bare + O `?`

`->` How long + have / has + S + V3 / ed + O `?`

`->` How long is it / has it been + since + S + V2 / ed + O `?`

`bb\4.` S +  have / has + V3 / ed +  O + for + time

`->` It is / It has been + (time) + since + S + V2 / ed + O

`-` S + have / has + not + V3 / ed +  O + for + time

`->` It is / It has been + (time) + since + S + last + V2 / ed + O

`bb\5.` The last time + S + V2 / ed  + O + was + (time)

`->` S + last + V2 / ed + O + (time)

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

`1.` Mr. Dake has bought a new car for three months.

`2.` When did you learn English `?`

`3.` This is the first time she has been to a French restaurant.

`4.` Sandra has worked at the post office for `2` years. 

`5.` I have never had an accident before.

`6.` She had done her homework for a few minutes. 

`7.` My father hasn't smoked for five years.

`8.` I have tried the running competition before. 

`9.` I haven't gone skateboarding before.

`10.` This is the first time I have seen such an interesting film.

`11.` We haven't seen grandparents for `2` years.

`12.` He had finished the work before he went out.

`@` S + had + V3 / ed, before + S + V2 / ed

`13.` When everyone had sat down, the talk show started.

Các công thức đổi HTHT - QKĐ

Structure 1: 

S + has/have + not + V3/ed + for/since + time 

--> S + last + V2/ed 

--> The last time + S+ V2/ed + was + time 

--> It is / has been + time + since + S+ (last) + V2/ed 

Structure 2: 

How long + has/have + S+ V3/ed?

--> When + did + S + V1?

--> How long is it + since + S+ V2/ed ?

Structure 3:

S + has/have + V3/ed + for/since + time 

--> S + started / began + to V / Ving 

--> It is / has been + time + since + S+ V2/ed 

Structure 4: 

S + has/have + not/never + V3/ed + ... before

--> This/It is the first time + S+ has/have+ V3/ed

------------------------------------------------------------------

1. Mr. Dake has bought a new car for three months.

2. When did you learn English?

3. This is the first time she has been to a French restaurant.

4. Sandra has worked at the post office for 2 years. (sửa đề: wake --> work)

5. I have never had an accident before.

6. She had done her homework for a few minutes. (sửa đề: few minutes --> a few minutes)

7. My father hasn't smoked for five years.

8. I've tried the running competition before. 

9. I haven't gone skateboarding before.

10. This is the first time I have seen such an interesting film.  (sửa đề: films --> film)

11. We haven't seen grandparents for 2 years.

12. He had finished the work before he went out.

QKHT +before + QKD

13. When everyone had sat down, the talk show started.

When + QKHT, QKD

`color{orange}{~MiaMB~}`