He _____________ for 3 hours before he finished his work.

Câu hỏi :

He _____________ for 3 hours before he finished his work.

A had been typing

B had been typed

C  had typing     

D typed

* Đáp án

A

* Hướng dẫn giải

Phương pháp giải:

Copyright © 2021 HOCTAP247