1Asateacher,Inevergivestudentssodifficultaquestion____theycan'tworkout.
Asateacher,Inevergivestudentssodifficultaquestion____theycan'tworkitout.
请问这两句话有什么区别?为什么第一个空填as,第二个空填that?
邮箱: 联系方式: