2009年职称英语综合类C级近义词组推荐电子书
notion - concept - idea 概念
characteristic - feature 特征
be characteristic of - be typical of 是….所特有的
difficult - hard - tough 困难的
notion - concept - idea 概念
characteristic - feature 特征
be characteristic of - be typical of 是….所特有的
difficult - hard - tough 困难的