He called for a clean fight in the election and an end to "negative campaigning."

他呼吁在竞选中公正交锋，停止“消极竞选”。

《柯林斯英汉双解大词典》

This is a clean fight.

这是一场公平的较量。

youdao

Win or lose, she will fight for better schools, better hospitals, for decent roads and clean water.

无论是赢还是输，她都将为更好的学校，更好的医院，像样的道路和干净的水而斗争。

youdao

They also announced plans to cooperate in efforts to fight climate change and develop clean forms of energy.

VOA: special.2009.04.18

The United States wants a relatively clean election while it considers whether to send more troops and resources to Afghanistan to fight the Taliban.

VOA: standard.2009.10.28

And in a further gesture of goodwill, the Chinese leader promised help in building 100 clean energy projects, part of what China says is its commitment to fight global warming.

VOA: standard.2009.11.08

Well it looks like in a relatively clean fight, Nokia has that role with Windows Phone.

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Mr Cameron also used his message to call for the general election campaign to be a "good clean fight".

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"I knew I was winning the fight clean, " Stevens said.

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