Bài 1: Chọn đáp án đúng:
Yesterday was the deadline that I ________ finish my chemistry project.
A. must
B. mustn’t
C. had to
D. have to
Susie will ________ wait in line to get a ticket for the concert. 
A. must
B. have to
C. has to
D. need
All employees in this factory ________ on time for work.
A. must be
B. mustn’t
C. have to
D. don’t have to
We ________ forget to turn off the air conditioner before going home.
A. have to not
B. must
C. mustn’t
D. ought to
If you are under 13 you _____ to get your parents’ permission.
A. need
B. must
C. musn’t
D. don’t have to