`1.` HTHT: I have written to him the past 2 years.

    HTHTTD: I have been writting to him the past 2 years.

`2.` HTHT: Where has he gone?

     HTHTTD: Where has he been going?

`3.` HTHT: You have stood in the rain.

     HTHTTD: You have been standing in the rain.

`4.` HTHT: Mr.Beson has fished yesterday.

    HTHTTD: Mr.Beson has been fishing yesterday.

`5.` HTHT: The company has losed money.

     HTHTTD: The company has been losing money.

`6.` HTHT: They haven't lived in the same town for over 20 years.

     HTHTTD: They haven't been living in the same town for over 20 years.

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`+` Cấu trúc thì Hiện tại hoàn thành: 

`(+)` Khẳng định: S + have/has + Ved/V3

`(-)` Phủ định: S + have/has + not + Ved/V3

`(?)` Nghi Vấn: Have/has + S + Ved/V3

`+` Cấu trúc thì Hiện tại hoàn thành tiếp diễn:

`(+)` Khẳng định: S + have/has + been + Ving

`(-)` Phủ định: S + have/has + not + been + Ving

`(?)` Nghi Vấn: Have/has + S + been + Ving...?