––Have you returned the book to the library ?––Yes I have returned it.A. yet yetB. alre

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：yet和already都表示已经的意思，区别是前者多用于疑问句和否定句，后者用于肯定句。句意：你已经把书还给图书馆了吗？——是的，我已经还了。结合语境可知选Ｄ。