Question

Having checked the doors were closed, and _______ all the lights were off, the boy opened the door to his bedroom.

A．why

B．that

C．when

D．where

Answer 1

B

解析试题分析：句意：已经检查了门是关着灯，所有的灯都关掉了，那个小男孩打开了卧室的门。这里and连接的是并列的两个checked的宾语，the doors were closed是checked的宾语，all the lights were off也是checked的宾语。第一个宾语的连词that可以省略，第二个连词不可以省略，that在从句中不作成分，因为这两个宾语从句的都不缺少成分。故选B。
考点：考查连词的用法。
点评：本题难度适中。判断宾语从句中用哪个连词，需用记住连词的用法，在句中的作用，连词也是高考的热点，需要考生平时多练习。需要考生会分析句子成分理解句意。
即学即练：I can’t come back________six o’clock perhaps. Don’t wait for me for supper. A. after      B. if         C. until       D. when
解析：C。until引导时间状语从句时常与not连用，意为“我大约直到6点才能回来”，故选C。