为什么He'll do what he can to study hard.这句话中What 不可以改成that
问题描述：
为什么He'll do what he can to study hard.这句话中What 不可以改成that
答
用 that 可以改为：
He'll do all that he can to study hard
还可以说：
He'll do whatever he can/it takes to study hard
答
翻译一下就知道。what he can（他所能的事）相当于do的宾语。that只是连词。
答
what引导宾语从句,作do的宾语,that不可以
而你可以说do everything THAT he can to...