1.political system 政治体系

例句：The Chinese political system has evolved over a long period of time.

中国的政治制度是长期发展形成的。

2.self-interested 利己主义的

例句：Even a self-interested army stands to gain more from a society that is more productive.

即便出于自私的军方立场来看，从一个更加多产的社会中，他们也会收获更多。

3.expect to 期待去做

例句：It doesn't work so well when we're not particularly motivated to achieve our goal or don't expect to do well.

当我们不是特别关注我们实现的目标或者不期望做得更好时，蔡加尼克效应将会失效。

4.come together 集合

例句：We have to come together, worldwide, and "think".

我们——全世界——必须联合起来共同思考。