The thief stole my wallet ________ I knew it.

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I had not been waiting very long _____ he returned from the conference in the town.

A．until     B．after            C．while          D．before

Let me say sorry to her? No way!1 would die      I apologize to her!

A．after             B．before                  C．until     D． while

Someone called me at midnight, but he hung up ________ I could answer it.

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