Sometimes travelers are stopped for having done something dubious to arouse the suspicion of authorities, but this student probably just happened to be part of the custom's random checks.

通常有可疑举动引起当局怀疑的游客会被拦下检查，但是这名学生可能只是碰巧被海关的随机检查抽中了。

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So consumers who want to eat shrimp are faced with two choices: trust that random spot checks find any problems with seafood imports or pay more for domestic, wild harvested shrimp.

VOA: standard.2010.05.27

The Independent's editorial urges authorities "to introduce more random checks... and tougher fines for those who break the rules".

BBC: Papers

There is absolutely nothing sinister about them - the idea is to make random checks to see how well the system is working.

BBC: Self assessment penalties and enquiries

Therefore testers make choices, to stay with the metaphor, they decide to check the main roads, to check Manhattan and to do some random checks.

FORBES: Machiel van der Bijl On Automated Software Testing