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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- Can I pay the bill by check? -- Sorry, sir. But it is the management rules of our hotel that payment ______ be made in cash.
#63577
A
can
B
shall
C
will
D
may
You can’t imagine that a well-behaved gentleman _____ be so rude to a lady.
#63110
A
should
B
must
C
might
D
would
— I know by what time you want the project to be done?—By the day after tomorrow. you finish it on time?
#74189
A
May; Can
B
Must; Need
C
Could; Must
D
Need; Would
— Isn’t that Ann’s husband over there? — No, it ________ be him — I’m sure he doesn’t wear glasses.
#62799
A
must not
B
can’t
C
won’t
D
may not