In a business setting, tipping is not optional. Consider tipping mandatory when it comes to business entertaining expenses. Even if service is substandard still leave at least some tip.

在商业场合，小费是必不可少的。商业招待费用中，小费是一笔固定的支出。即使服务是不合格的，也要记得给一些小费。

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Chung is expected to say that much of the money went to pay for his own business expenses as well as the costs associated with entertaining the various Chinese business groups that sought to do business with him.

CNN: Chung testimony: I'm not a Chinese agent