问题
选择题
— I am going to the dentist at 4 o'clock and it is 3：30 now.
— Well, if you ______ leave earlier today, please ask the director for permission.
A．can
B．may
C．must
D．will
答案
答案：C
考查情态动词。must在这里是“偏要”的意思。故选C。