- When did they come back last night?- It was midnight all of us were sleepingA.
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— When did they come back last night?
— It was midnight ____ all of us were sleeping
A.that
B.when
C.which
D.in which
试题答案
B
考查定语从句。根据先行词midnight为从句逻辑时间状语，可知选B。