I ( know) have known her for six years, when I met her, she (work) was working for a foreign company.

⇒Vế trước THTHT 

⇒Dấu hiệu: for six years

⇒S+ have/has+ Vp2

⇒Vế sau : When+ S + V(QKĐ)…,S + V(QKTD).

Hành động xảy ra trước một hành động khác.

VÍ DỤ: When I went out, my mother was cooking for lunch.

MĐ `1` : I have known her for six years

`\rightarrow` Thì HTHT : S + have / has + VpII

`\rightarrow` For + Khoảng thời gian

MĐ `2` : When I met her , she was working for a foreign company

`\rightarrow` When + S + Ved / V2 , S + was / were + V-ing

`=>` Dùng để diễn tả hành động đang xảy ra , hành động xảy ra trong một lúc

`\text{# Kirigiri}`