The benefits are hard to detect.

其好处却很难被察觉。

youdao

Unfortunately, they are hard to detect.

不过遗憾的是，观测它们相当困难。

youdao

Even then, the invaders are hard to detect.

即使如此，这些入侵者仍难以觉察。

youdao

Sewn into custom-made underwear, it would have been hard to detect during a pat-down.

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The Ministry of Defence (MoD) said it "works hard to detect and deter theft".

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But the increase in risk, at something like 40%, is modest and hard to detect.

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