Mr. Li asks the students in the river because it’s too dangerous.A. swimB. to swimC. not

问题补充：

Mr. Li asks the students in the river, because it’s too dangerous.

A. swim

B. to swim

C. not to swim

D. to not swim

答案：

A. swim

B. to swim

(答案→)C. not to swim

D. to not swim

解析：本句的含义为李老师叫学生们不要在河里游泳，因为太危险了，ask sb not to do表示叫某人不要做某事的含义，故本题选C。