题目

 He went into his room,     the light and began to work.   A. has turned on   B. turned off   C. turned on   D. has turned off 答案：C 解析:时态、动词短语的考察 进房间，开灯、开始工作一些列的顺成动作，均用一般过去时，在反比例函数的图象上有两点A（x1，y1），B（x2，y2），x1＞x2＞0时，y1与y2的大小关系是y1    y2．