however引导让步状语从句时,相当于nomatterhow,后面跟形容词或副词;as引导让步however引导让步状语从句时,相当于nomatterhow,后面跟形容词或副词；as引导让步状语从句时,用倒装语序,即把作状语

Question

however引导让步状语从句时,相当于no matter how,后面跟形容词或副词;as引导让步
however引导让步状语从句时,相当于no matter how,后面跟形容词或副词；as引导让步状语从句时,用倒装语序,即把作状语的副词或作表语的形容词或名词提前,而且如果作表语的是单数名词,前面不加冠词,也可以把谓语动词部分的实义动词提前.
[误] As hard he works,he can’t catch up with his classmates.
[正] However hard he works,he can’t catch up with his classmates.
问：为何As hard he works,是错的,根据上面讲的,as引导让步状语从句时,用倒装语序,即把作状语的副词或作表语的形容词或名词提前,这些都满足呀

Answer 1

as表示虽然的时候,需要倒装, as不能位于句首.应该是 ：Hard as he works,.