I believe this to be a profound mistake.

我认为这是莫大的错误。

youdao

This is a profound mistake and one we will all pay dearly for in the long run.

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Expansion will be a profound mistake, putting at risk the economic and strategic purposes I have referred to.

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He said the decision to scrap the Harriers was "a profound mistake" and condemned the loss of Nimrod as an "unacceptable risk", warning the UK would be less able to deal with the threats it faced.

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