第27题: [单项选择]At first, the speaker was referring to the problem of pollution in the country but halfway in her speech, she suddenly ______ to another subject. A. committed B. favored C. switched D. transmitted 参考答案:C 答案解析:题意是:起初,演讲者提到该国的污染问题,但是在其演讲中途,她突然到另一个话题。[C]switched“转换,改变(话题,思路等)”,符合题意。[A] committed“犯(罪),委托”,[B]fav