I am sitting on the cusp of middle age.

我正处于中年。

《柯林斯英汉双解大词典》

But we now stand on the cusp of an even larger congressional blunder: cap-and-trade.

不过，我们现在正站立在国会犯大错的尖顶：施行限制排放与交易许可法规。

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We are on the cusp of a major revolution.

我们正处于一场重大变革的风口浪尖。

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He said all sides were "on the cusp of agreement" on a financial package to fund the transfer of the powers.

BBC: Policing talks 'make progress'

He came of age on the cusp of the 1960s, when women and their like-minded male friends began to embrace and promote the idea of sexual equality.

CNN: Same-sex couples take long road to the altar

With three distinct major groups--and two of these on the cusp of allout war--not to mention several smaller minorities, Iraq must have local autonomy in the style of Switzerland (or Bosnia) if the country is to have a peaceful future.

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