The issue of sovereignty is a red line that cannot be crossed.

主权问题是一条不能跨越的红线。

《牛津词典》

Three horses crossed the finish line together.

3匹马同时冲过终点线。

《柯林斯英汉双解大词典》

Then they crossed the state line into Mississippi.

然后他们跨越州界线来到了密西西比州。

《柯林斯英汉双解大词典》

Vonns teammate,Julia Mancuso, crossed the finish line less than a second later for the silver medal.

VOA: special.2010.02.26

That line had clearly been crossed and helps explain why it was that in a country in which there weren't ten people who wanted a republic in 1789.

绝对主义和专制主义的区别已经不存在,这解释了为何在这个国家,1789年时只有不到十人想建立共和制

耶鲁公开课 - 欧洲文明课程节选

So, he had crossed the line. And as an ordinary soldier.

他逾越了本分,以普通的士兵的身份

耶鲁公开课 - 古希腊历史简介课程节选

And what might have started out being innocent, if you accept that argument, crossed the line -- crossed the line -- whenever it was tied and interconnected with the president's desire to get a false affidavit from Monica Lewinsky.

CNN

The Parents Television Council yesterday cried foul, saying the shoot crossed the line.

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How will you know when you've crossed the line and allowed ambition to go too far?

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