When he the door, he found his keys were nowhere. A. would open B. opened C. had

When he  _______ the door, he found his keys were nowhere.                        

A. would open           B. opened                 C. had opened           D. was to open

试题答案

D

解析:

考查非谓语动词。动词不定时的用法。句意为：当他要打开门的时候,他发现他的钥匙不见了。动词不定时表示将要发生的动作。