Foreign officials who watch Venezuela closely say that Cuban agents occupy key posts in Venezuela's military intelligence agency, but these claims are impossible to verify.

近距离观察委内瑞拉的外国官员表示古巴军官在委国军情局担任要职，但这些说法未能得到证实。

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The claims were impossible to verify.

但这些说法无法得到证实。

youdao

They said they gave up their Kalashnikovs without a fight. They had been well treated by their captors, they added, although it was impossible to verify this independently.

他们说自己没有开火就交出了武器，还说俘获他们的人给予了恰当的待遇，不过后者显然难于印证。

youdao

It is impossible to verify who precisely is driving the demand for Chinese consumer goods.

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They are systems not suited to preemptive warfare and their deployments are impossible to verify effectively.

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Finally, it is impossible to verify a ban that extends to very low yields.

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