Mr. Ralph mathematics before he to literature.

A. had taught – had changed
B. was teaching – changed
C. taught – was changing
D. had taught – changed

Đáp án đúng: D

Thì quá khứ hoàn thành diễn tả một hành động diễn ra trước một hành động trong quá khứ.
Ông Ralph đã dạy môn toán trước khi ông chuyển sang môn Văn.

Số bình luận về đáp án: 0

Mr. Ralph ________ mathematics before he ________ to literature.

Mr. Ralph mathematics before he to literature.