There are no hard and fast rules, but rather traditional guidelines as to who pays for what.

关于谁来支付什么费用并没有一定要遵守的规定，只有传统的准则。

《柯林斯英汉双解大词典》

The client who pays for the building and defines its function is an important member of the architectural team.

为建筑付款并定义其功能的客户是建筑团队的重要成员。

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If he tells us it is safe, on the other hand, we distrust him, because he may well be protecting the employer who pays his salary.

另一方面，如果他告诉我们这是安全的，我们就不信任他，因为他很可能是在保护支付他薪水的雇主。

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They get their health care from the emergency room. And do you know who pays for that?

VOA: standard.2009.07.21

But big questions is who cuts,by how much, who pays and what it will cost.

VOA: standard.2009.12.06

The first pride of a man is to do well for the guy who pays you.

BBC: Club needs to come first - Wenger

But who pays for this failure to enter the 21st century and accept reality?

FORBES: How Health Regulators Are Killing American Smokers

The real question is, who pays these refinancing costs and how exactly do they get paid?

FORBES: The No-Cost Refinancing Myth