题目内容
If you want to do the experiment a second time, you'd better be more careful ________ you made a mistake.
[ ]
A.
when
B.
in case
C.
where
D.
unless
答案:C
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题目内容
If you want to do the experiment a second time, you'd better be more careful ________ you made a mistake.
when
in case
where
unless