He is a good student except___he is sometimes careless.空处为什么填that而不填which,except不是介词吗
问题描述：
He is a good student except___he is sometimes careless.空处为什么填that而不填which,except不是介词吗
答
except是介词,但此处需要一个宾语从句的引导词,而which是用来引导定语从句的.