He tends to act on impulse.

他往往凭一时冲动行事。

《牛津词典》

Sean's a fast thinker, and he acts on impulse.

肖恩是个思维敏捷、凭一时冲动行事的人。

《柯林斯英汉双解大词典》

Quite often we do things on impulse.

我们做事往往很冲动。

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Usually, the metrical impulse is on the beat.

一般来说,韵律的冲动出现在节拍上

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But the court heard he left the prison on impulse after he was refused parole.

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"Too many of us buy sunglasses on impulse, let's say at an airport, " he says.

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The emergence of lower-priced tablets is also encouraging consumers to purchase the devices on impulse, Allenson theorizes.

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