Sometimes it is now or never.

有时没有此时就没有了未来。

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Sometimes there is no next time, no second chance, no time out. Sometimes it is now or never.

有时候，没有下一次，没有机会重来，没有暂停继续。有时候，错过了现在，就永远永远的没机会了。

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Sometimes it made us sad when he was growing up because we thought he would never be able to do normal things like ride a bike or drive a car, but now he is so popular, and that has made us happy.

有时候他使我们感到悲伤，因为我们认为当他长大，他连做一些正常人能做的事情如骑单车、驾驶汽车都不行，但是现在他是如此受欢迎，并让我们很高兴。

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In Chamberlain's final year before free agency, it is now or never for the one-time phenom to prove he should be part of the Yankees' future.

WSJ: New York Yankee Reliever Joba Chamberlain Trying To Bury the Hatchet

For the FN leader, Marine Le Pen, it is a now-or-never moment.

BBC: The struggle to get France working again