Nobody knows for sure how dinosaurs died out 65,000,000 years ago. It _______ because of sudden changes of their living conditions.
#62591
A
must have happened
B
would have happened
C
should have happened
D
might have happened
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—May I smoke here? —If you _____, choose a seat in the smoking section.
#62987
A
should
B
could
C
may
D
must
Mr Black be at home because she called me from England just now.
#76189
A
mustn't
B
isn't able to
C
can't
D
may not
Next week, there ____________ a different New Year party on HNTV.
#77148
A
is going to be
B
are going to have
C
is going to have
D
are going to be
—Excuse me，but I haven’t got the iPhone 4 ordered through the Internet． —Sorry madam,I’m sure you have it by this Friday．
#63588
A
must
B
may
C
could
D
shall
— May I take the magazine out of the reading room? — No, you can’t. You _________ read it here. It’s the rule.
#78142
A
must
B
would
C
may
D
might