There're students in Grade7.
A. three hundreds
B. three hundreds of
C. three hundreds'
D. hundreds of
网友回答
A. three hundreds
B. three hundreds of
C. three hundreds'
(答案→)D. 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.