`a)`I haven’t heard him since August.

`->` The last time I heard him was in August.

`b)`  I haven’t seen him since I was a student.

`->` I last saw him when I was a student.

`=>` Cấu trúc chung :

The last time + S + V2 was + khoảng thời gian + ago

`=` S + last +V2+ khoảng thời gian + ago

`=` S + have/ has not = haven't/ hasn't + V2 + for + khoảng thời gian

`=` It's + khoảng thời gian + since + S + V2

`=` The last time + S + V2 + was + mốc thời gian trong quá khứ

`=` S + last + V2 + thời điểm trong quá khứ 

Áp dụng cấu trúc đó để làm các bài tập dưới :

`1.` I haven’t played football since 1970.

`=>` The last time I played football was in `1970.`

`2.` We haven’t seen Tom since he moved to Bristol.

`=>` We last saw Tom when he moved to Bristol.

`3.` It hasn’t rained for a fortnight.

`=>` The last time it rained was fortnight ago.

`=>` It last rained was fornight ago.

`4.` Lucy hasn’t worn that dress since Barbara’s wedding.

`=>`The last time Lucy wore that dress was in Barbara's wedding.

`5.`My father hasn’t been to Vung Tau for 2 years.

`=>` The last time my father went to Vung Tau was `2` years ago.