1.fret about 烦恼；担心

例句:You had better not fret about your mistakes.
你最好不要为你的错误而烦恼。

2.nuclear weapon 核武器

例句:We have conducted a new nuclear weapon test successfully.
我们成功地进行了一次新的核武器试验。

3.strike against 打击

例句:They went on strike against the oppressive regulation.
他们罢工以示他们对这不公平的规则的反抗。

4.international order 国际秩序

例句:Everyone understood the shared interest in sustaining a rules-based international order.
大家都明白，维持一种建立在规则基础上的国际秩序符合各方的共同利益。