It is impossible to say who struck the fatal blow.

不可能确定是谁给了那致命的一击。

《柯林斯英汉双解大词典》

We gave the enemy a fatal blow.

我们给敌人以致命的打击。

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But it was the Internet that struck the fatal blow.

而互联网则更是给出了致命的一击。

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sanctions resulting from the launch will deal a fatal blow to six-nation talks aimed at ending the North's nuclear weapons programs.

VOA: standard.2009.03.27

And,Israeli Prime Minister, Benjamin Netanyahu has warned the United Nations would deal, what he called, a fatal blow for Israeli-Palestinian peace if it endorses the report.

VOA: standard.2009.10.03

The UN has warned the homes would be "an almost fatal blow" to peace hopes.

BBC: UK and France summon Israeli envoys in settlements row

On dismounting, he fell and received a fatal blow in the stomach from the horse.

FORBES: Magazine Article

Midfielder Geremi, who had been influential throughout, then dealt his team a fatal blow.

BBC: Egypt 3-1 Cameroon (aet)