The children do not know how to themselves decently at the party.A. actB. performC. behav

问题补充：

The children do not know how to themselves decently at the party.

A. act

B. perform

C. behave

D. advance

答案：

A. act

B. perform

(答案→)C. behave

D. advance

解析：考查动词辨析：A. act行动，B. perform表演，表现，C. behave行为举止D. advance进步，behave oneself举止得体，句意是：孩子们不知道怎么在聚会上行为举止有礼貌。选C。