Question

He must have gone out. I heard the noise of the door ______when I was still in bed.

A．being locked

B．to lock

C．locking

D．having locked

Answer 1

A

考查非谓语动词和固定用法。句意“他一定是出去了。当我没起床时，我就听见了锁门声。”door和lock之间是被动关系，应该用被动语态。hear sb./sth. doing sth.“听到正在做某事”。故选A。