He shouted after them, vainly trying to attract their attention.

他在他们的后面高喊，想引起他们的注意，却是徒劳。

《牛津词典》

He hunted vainly through his pockets for a piece of paper.

他徒劳地摸索着自己的口袋想找到一张纸。

《柯林斯英汉双解大词典》

The criminals vainly sought concealment from the searchlight.

罪犯们试图躲开探照灯光，纯属徒劳。

《柯林斯英汉双解大词典》

Meanwhile, Sun's beleaguered sales force is vainly trying to extract profit from its new severs.

FORBES: Microsoft's War Of Attrition

Even as terror struck Algiers, Camus was vainly urging a federal solution, with a place for French settlers.

ECONOMIST: In search of the real Camus

It is thought to have been left by a pair of Australopithecus afarensis, vainly retreating from an erupting volcano.

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