Do what you can to help him.这里的what you can 是宾语从句 为什么不是 what you can do 呢

题目

Do what you can to help him.这里的what you can 是宾语从句 为什么不是 what you can do 呢

答案

这句话的主结构是：Do sth.to help him.
中间加上what you can 替换sth.
Do what you can do to help you.也是正确的,
只是后来省略了.