Cuuuuuauuuuuuuuuuuuu

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

`***` Thì HTHT : 

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

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

`(+):` S + have/ has + VpII

`(-):` S + have/ has + not + VpII

`(?):` Have/ Has + S + V3 `?`

       WH-word + have/ has + S (not) + V3 `?`

`->` S = I/ We/ You/ They + have

`->` S = He/ She/ It + has 

`@` 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)

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

 `----------`

`1.` She hasn't seen her elder sister since `1999.`

`2.` I have never seen this film before.

`3.` The last time she wrote to US was last year.

`4.` I haven't had such a delicious meal before.

`5.` I haven't gone swimming since we were in our hometown.

`6.` We haven't been to a night club before.

`7.` The last time we went to a concert was over a year ago.

`8.` The last time i went to Taiwan was `2` years ago.

`9.` It is the first time I have been to this place

`10.` I haven't gone swimming since I was in Hue.

Đáp án:

1 she hasn't seen her elder sister since 1999

2 I have never seen this film before

3 the last time she wrote to US was last year

4 i haven't had a such a delicious meal before

5 i haven't gone swimming since we were in our hometown

6 we haven't been to a night club before

7 the last time we went to a concert was over a year ago

8 the last time i wnet to Taiwan was two years ago

9 it is the first time I have been here

10  i haven't gone swimming since I was in Hue city