It was, as secret weapons often are, hugely expensive.

正如所有的秘密武器，它费用不菲。

youdao

Concrete may well have been one of the secret weapons of the Roman Empire.

混凝土也许一直是罗马帝国的秘密武器之一。

youdao

It's part of that reconciliation, to do a peaceful survey of these secret weapons.

这是和解的一部分，做这些秘密武器和平的调查。

youdao

One of Silicon Valley's secret weapons is its openness to immigrants and to women.

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She wondered if her knowledge of munitions and secret weapons projects from her time in Austria could help somehow.

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Equally significant was Mr Qaddafi's decision, in 2003, to let British and American experts take apart his secret weapons programme, bringing a windfall of information about global smuggling networks.

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