When the teacher came into the classroom, the students .
A. stop to talk
B. stopped to talk
C. stopped talking
D. stop talking
网友回答
A. stop to talk
B. stopped to talk
(答案→)C. stopped talking
D. stop talking
解析：此题重点考查两个短语stop to do sth和stop doing sth的区别，前者表示停下来去做某事，后者表示停止做某事。根据语境可知此句的含义是当老师走进教室的时候，学生们都不讲话了，故选C。