问题补充:
He went into his room, the light and began to work.
A. has turned
B. turned off
C. turned on
D. Has turned off
答案:
A. has turned
B. turned off
(答案→)C. turned on
D. Has turned off
解析:turn转动,转变;turn off关掉;turn on打开。句意;他走进他的房间,打开灯,开始工作。联系上下文,可知本句描述的是过去的动作,故用一般过去时态。选C。