For example, maybe in the future a robot nanny will replace a real human nanny, who are work more effective and without any complain.

例如，也许在未来机器保姆会替代人类保姆，它们工作更有效率，毫无怨言。

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Then on a morning as normal as always, however, he realized suddenly that how much his wife had sacrificed and contributed to this family during the long time of four years without any complain.

然而，在一个再平常不过的早晨，作者却突然意识到在长达四年的时间里，妻子毫无怨言地为这个家付出了多少。

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Depending on the price, the service offers a customer the chance to complain to the worker within a limited period without any boundaries as a way of releasing anger or stress.

根据不同的价位，顾客可以在固定时间内，无拘无束地向店员抱怨，以此释放愤怒和压力。

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