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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---Where is my pen?--- I _____it.
#63405
A
might lose
B
wouldn’t have lost
C
should have lost
D
must have lost
—“Crash diets” make us lose weight fast and I am all into that. —But it_______better to work out.
#62644
A
had
B
would be
C
wouldn’t have been
D
must have been
— No wonder you caught a cold. You __________ out last night without a coat. — I know how silly I was.
#63493
A
should have gone
B
shouldn’t have gone
C
can’t have gone
D
mustn’t have gone
—Where did you meet him?—I met him on a number eleven bus, if you know.
#63394
A
can
B
must
C
shall
D
may
---Are you pleased with the result of the math exam? ---Not at all. I can’t have ______ one.
#75040
A
a worse
B
a better
C
the best
D
the worst