This is the checkout where all the food is paid for.1.请问已经是被动了,为什么句子结尾还留一个for?2.这个句子可以改用which吗?这样2个介词叠在一起吗?This is the checkout which all food is paid for at?
I am enclosing an application form, which I should be grateful if you would sign and return. 这里的 which 是引导非限制性定语从句吧?它的先行词是什么?或者说它修饰的是什么?这个 which 在从句中作什么成分?