1. It's a week since he last smoked a cigarette. -> He -> The last time 2. I last heard this song 10 months ago. -> I have -> The last time

1. He hasn't smoked a cigarette for a week

The last time he smoked a cigarette was a week ago

2. I haven't heard this song for 10 months

The last time I heard this song was 10 months ago

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Cấu trúc tương đương

- S have/has not VPII for...

- The last time QKĐ was...

`1. ->` He hasn't smoked a cigarette for a week.

`->` The last time he smoked a cigarette was a week ago.

`2. ->` I haven't heard this song for 10 months.

`->` The last time I heard this song was 10 months ago.

Cấu trúc: It's + time + since + S + last + V2/V-ed + ...

`->` S + hasn't/haven't + VpII + ... + for + time

`->` The last time + S + V2/V-ed + ... + was + time + ago

`->` S + last + V2/V-ed + ... + time + ago