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The bird fluttered its wings up and down.

那只鸟上下地拍动翅膀。

youdao

A ladybug in flight beats its wings up to 85 times per second.

瓢虫飞行时每秒钟扇动翅膀85次。

youdao

Voyager's long wings moved up and down as the winds changed.

VOA: special.2010.10.06

"Some are just sweeping and cleaning,carrying things. Other people,as you can see, are way up high up on the scaffolds putting wings on the eagles.

VOA: standard.2009.12.30

But it appears to be a catalyst-driven chemical system that releases both heat and gas in sufficient quantities to pump the wings up and down.

ECONOMIST: A personal eye in the sky

We pull (the wings) up, pull them down, add weight to them and take them right to the point of breaking.

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Its four carbon fiber and foil wings beat up to 20 times per-second, propelling it through the air as if it were swimming rather than flying.

ENGADGET: BionicOpter dragonfly drone flutters about, blows minds