`1,` It's over 3 months since Tom (last) had his hair cut.

`2,` It is 2 years since my father (last) went to Hanoi. 

- be to + địa điểm = go to + địa điểm

`3,` It is years since I (last) enjoyed myself so much.

`4,` It is 2 years since I (last) ate this kind of food.

`5,` It is hours since Mary (last) rang.

`@` Cấu trúc:

- It's + thời gian + since + S + (last) + Ved/V2 + O

= S + has/have + not + Vpp + for + thời gian

`1.` It's over `3` months since Tom last had his hair cut.

`2.` It is `2` years since my father went to Hanoi.

`3.` It is years since I last enjoyed myself.

`4.` It is `2` years since I ate this kind of food.

`5.` It is hours since Mary last rang.

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

`-` Cấu trúc bài trên:

`-` S `+` have/has `+` not `+` Ved/C3 `+` for `+` khoảng thời gian

`->`Ai đó/ sự vật gì/ hiện tượng gì đã không … trong khoảng …

`=` It's `+` khoảng thời gian `+` since `+` S `+` last `+` Ved/C2

`->` Đã bao lâu kể từ khi ai đó làm gì lần cuối ...