`1`.Samuel has kept a diary since 1997

`\rightarrow` Thì HTHT : S + have / has + V3 / PII

`\rightarrow` Đặc điểm nhận dạng : since

`2`.We have learned English for five years

`\rightarrow` Thì HTHT : S + have / has + V3 / PII

`\rightarrow` Đặc điểm nhận dạng : for

`3`.I have lived in Ho Chi Minh City since I was 8

`\rightarrow` Thì HTHT : S + have / has + V3 / PII

`\rightarrow` Đặc điểm nhận dạng : since

`4`.She started teaching the children in this remote village five months ago

`\rightarrow` Thì QKĐ : S + Ved / V2

`\rightarrow` Đặc điểm nhận dạng : ago

`5`.The last time he wrote to me was in April

`\rightarrow` Cấu trúc : The last time + S + Ved / V2 + was + time / in time

`\text{@ Fox}`