问题补充：
---I’d like to buy a book named Confucius from the Heart.
-- Sorry, it two days ago.
A. is sold out
B. has been sold out
C. was sold out
D. sold out
答案：
A. is sold out
B. has been sold out
(答案→)C. was sold out
D. sold out
解析：
试题分析: 句意：我想买一本名叫《论语>心得》的书。对不起，两天前售光了。sell out售光，根据 two days ago可知是一般过去时，it指代书，被售光，故选C.
