He brought his arm up in a futile attempt to ward off the blow.

他出于挡住这一击的无谓企图抬起了他的胳膊。

《柯林斯英汉双解大词典》

They are a futile attempt to keep from missing out.

企图阻止错过是徒劳无益的。

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The pedal is moving up and down, stiffly, automatically, a crazy, futile movement, like a tower of dung that takes twenty seven years to build but keeps perfect time.

钢琴踏板在僵硬地、机械地上下移动，这是一种疯狂的、徒劳无功的运动，像花了二十六年时间堆起来的一堆大粪，不过却是准时完工的。

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He says if libel remains a criminal offense, then even a Freedom of Information law is futile.

VOA: standard.2009.12.28

By the way, once again there's a bit of a rift there between Barthes and Foucault. Foucault wouldn't say "quite futile."

顺便说一句，这里巴特和福柯,又有了分歧，巴特不会说“没有希望“

耶鲁公开课 - 文学理论导论课程节选

It tells you that any attempt to try to specify, to localize the position of an electron in such a system is futile.

这说明你试着任何尝试关于，使一个电子在这样一个系统中,确定其明确的位置是没有意义的。

麻省理工公开课 - 固态化学导论课程节选

Perhaps this is too futile a goal and art is not enough of an action to be an actual catalyst for change.

CNN: An 'Afghan redneck' creates art in a war zone

In a sequence that really said it all, point guard Raymond Felton found a wide-open Tyson Chandler for an alley-oop, but Chandler somehow missed the dunk, then fumbled a futile effort at a put back.

WSJ: N.Y. Knicks: The All-Star Break Is Over, Right?

Unfortunately, the Achilles heel of this strategy is that it depends on the retailer to set up and maintain the signage often a futile hope, while at the same time a critical portal for the shopper.

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