It was nearly an hour the sleeping pill effect. A. when; took B. before; took C.
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It was nearly an hour ____the sleeping pill ______effect.
A. when; took B. before; took C. since; had D. before ; had
试题答案
B
解析:
It was+一段时间+before…表示“过了….才…”take effect 表示（药等）见效；（法规等）生效