问题补充：
--How many birds can you see in the tree?
--I can seebirds in the tree.
A. hundred of
B. hundreds of
C. five hundreds
D. five hundreds of
答案：
(答案→)A. hundred of
B. hundreds of
C. five hundreds
D. five hundreds of
解析：此题考查名词的量。确切数量常用数词+hundred/thousand/million/billion+名词的复数形式；不确切数量常用hundreds/thousands/millions/billions + of+名词的复数形式.
