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Các công thức đổi HTHT - QKĐ

Structure 1: 

S + has/have + not + V3/ed + for/since + time 

--> S + last + V2/ed 

--> The last time + S+ V2/ed + was + time 

--> It is / has been + time + since + S+ (last) + V2/ed 

Structure 2: 

How long + has/have + S+ V3/ed?

--> When + did + S + V1?

--> How long is it + since + S+ V2/ed ?

Structure 3:

S + has/have + V3/ed + for/since + time 

--> S + started / began + to V / Ving 

--> It is / has been + time + since + S+ V2/ed 

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21. John has been playing the organ for five years.

22. We started cooking for the party four hours ago.

23. The last time she played the piano was five years ago.

24. When did you last see Peter?

25. The last time I went to London was when I left my college.

26. We have been cooking for the party for four hours. 

27. When did you buy the house? 

28. We haven't decorated this room for years.

29. It's three months since she last went to the hairdresser.

30. They haven't visited me for five years.

31. The last time I went to Bristol was 3 years ago.

32. My sister began studying French 2 years ago.

33. It's 4 years since Robert and Catherine got married.

34. She has left university for 2 years.

35. When did you last see Mary? 

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