The students began classifying books in the library when the teacher came.
=> The students have……………………………………………………………….
When did you start teaching in this school ?
=> How long ……………………………………………………………?
. Minh has studied French for 2 years .
=>Minh began………………………………………………………
The students began classifying books in the library when the teacher came.
=> The students have classified books in the library when the teacher came.
When did you start teaching in this school ?
=> How long did you teach in this school?
Minh has studied French for 2 years .
=>Minh began stuyding 2 years ago.
→The students have been classifiying books in the library when the teacher came. (S + started / began + Ving / toV →S + have PII / have been + V-ing)
→How long is it since you start teaching in this school?( How long is it since=when did)
→Minh began learning French 2 years ago.(S + started / began + Ving / toV )