Apples are usually sold by --C-weight,and eggs are sometimes

问题描述：

Apples are usually sold by __C_weight,and eggs are sometimes sold by ___dozen.
A the the B \ a C \ the D the a
请高手给个确切的答案,在讲下其中的语法知识,为什么不选B呢,

1个回答分类：英语 2014-10-12