Mark the letter A, B, C or D to indicate the correct answer to each of the following questions.

Câu hỏi

Recently, a new vaccine against measles _____ .

A. has been developed

B. had been developed

C. had developed

D. was developing

Đáp án
A. has been developed

Câu hỏi thuộc Bài tập:

[049] - GRAMMAR - Ôn thi Giữa Học kỳ 2 - Tiếng Anh lớp 12 (Chương trình SGK mới)