罪犯们非常不愿意留下案底。

Criminals are very reluctant to leave a paper trail.

《柯林斯英汉双解大词典》

这样一来，当有案底的人群到达机场，就不必每次都把所有的精力都放在他们的安检上，对于风险较低但仍有风险的人物，也可以放过。

That means you do not expend all your resources checking only one tiny group of people every time they turn up at an airport - and hardly ever checking people who pose a lower risk, but still a risk.

youdao

好像这是不够的，业务解决方案底层的技术在不断的演进。

As if this weren't enough, the underlying technology for business solutions is continuously evolving.

youdao

Over a third had official records and 20 more percent had unofficial records for misdemeanors.

超过三分之一有案底,超过20%犯轻罪，无案底。

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