问题补充:
--Have you returned the book to the library ? --Yes, I have returned it.
A. yet, yet
B. already, already
C. already, yet
D. yet, already
答案:
A. yet, yet
B. already, already
C. already, yet
(答案→)D. yet, already
解析:句意:你已经把这本书还给图书馆了吗?是的我已经归还了。yet用于疑问句,已经,用于否定句,还;already,用于肯定句,已经。故选D