The government of the United States began at once to investigate the case ______ a lot of students were killed.
#77430
A
that
B
when
C
where
D
why
推荐题目
I can never forget the days _____ we worked together and the days ______ we spent happily together.
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A
for which; that
B
which; when
C
when; which
D
on which; when
I can’t thank him too much, ____________ I couldn’t have finished the project in time.
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A
without his help
B
with his help
C
without whose help
D
with whose help
At the party,John made up a joke,________ people burst out laughing. 
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A
on which
B
by which
C
at which
D
from which