EXERCISE 3I. CHỌN TỪ/ CỤM TỪ THÍCH HỢP (ỨNG VỚI A, B, C, D) ĐỂ HÒAN TH...

41. He started working as a teacher five years ago.

A. He has been working as a teacher for five years.

B. He has worked as a teacher since five years.

C. He is working as a teacher since five years.

D. He had been working as a teacher for five years