问题
选择题
When the teacher walked into the classroom, the students ____ at once.
A．stopped to talk
B．stopped talking
C．stop to talk
D．stop to talking
答案
答案：B
当老师走进班级，学生们应该立刻停止说话，stop doing sth表示停止做某事，与本题题意相符，故本题选B。