Whenever someone asks you something you don't want to answer, smile and ask "why do you want to know".

当有人问了你不愿意回答的问题时，请微笑着问他：“你为什么想知道？”

youdao

We never talked much, he would just simply smile and ask what else he could do, then thank me for letting him stay and slowly head for home.

我和他说话很少，他一般是笑着问我还需要他做些什么，然后感谢我让他留下来做事，接着就慢慢地往家去了。

youdao

And when a campaigner tells you in his stump speech that he thinks taxes should be raised, smile sweetly and ask him how much he added to his tax bill last year.

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If you congratulated him, he'd say thanks, smile, shrug and ask about you instead.

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Next, ask to speak to a supervisor and repeat your request with a smile on your face.

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