—I don't know_________to do with this maths problem. It's too hard.

—I don't know_________to do with this maths problem. It's too hard.
— You can ask your classmates or teachers for help.
A. which B. how C. what D. when
答案选C 大家帮忙分析一下what how ~~

你把疑问句改成陈述句看看：
to do___with this mathe problem。
do是及物动词，所以后面得接宾语，宾语得是名词性质的，就是what啦，how是用作状语的。。
加油学哦

dont know what to do就是不知道怎么办，所以选what. which是什么，how是怎么，when是什么时候，都搭不上。

译文：我不知道该拿这个数学问题怎么办。 what和do with 连用； how和deal with 连用,都是‘怎样处置’的意思。 如：我不知道该如何处理这个问题 i don't know what to do with the problem. i don't know how to deal with the problem.

how to deal with 和 what to do with 固定搭配