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
area – field 领域
area – region 区域
final –last 最后的
diploma – certificate 证书
pleasing – satisfactory 令人满意的
wish – hope 希望
massive – extensive – a mass of -- plentiful大量的
conference – meeting会议
close – intimate -- near亲密的
link – connect 连接
explore – investigate 调查