题目

Seeing their son playing computer games all day, the parents don’t know ______ it. A. how to do B. what to do C. how to deal with D. how to do with   答案：C从句意和结构看，使用do with或deal with都可以，但do with不可与how连用。   如图所示的四种现象的形成，属于凝华的是 [　　] A． B． C． D．