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

Câu hỏi

People living in the high building______obey the safety rules and regulations strictly.

A. shouldn't

B. have to

C. mustn't

D. must

Đáp án
B. have to

Câu hỏi thuộc Bài tập:

E11- GS- Review (after unit 5)