try one's best同义词He tried his best to help us.He ( ) ( )he could to help us可以讲下原因么，
问题描述：
try one's best同义词
He tried his best to help us.
He ( ) ( )he could to help us
可以讲下原因么，
答
He did what he could to help us.
答
spare no efforts to do
比try one's best稍微高级点,意思是不遗余力地做某事
答
did what
下句用了个宾语从句what he could 做did的宾语
也可以说he did his best to help us
to help us 都表示目的状语
答
did what
答
did ,what
答
He (did) (what)he could to help us.
这句话完整的说是 He did what he could do to help us. 其中what he could do 是一个宾语从句 句中do 可省略.