Opponents worry that such expansion would be costly for taxpayers, but advocates say it would save money in the long run.

反对者担心这样的扩张会让纳税人付出高昂的代价，但支持者说，从长远来看，这种扩张可以节省资金。

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Having curtains made professionally can be costly.

找专业人员制作窗帘会很贵。

《柯林斯英汉双解大词典》

Having professionally made curtains can be costly, so why not make your own?

买专业制造的窗帘可能很贵，你为什么不自己做呢？

《柯林斯英汉双解大词典》

These fees can be costly even if you overspend by just a few cents.

VOA: special.2009.05.21

Governments establish regulators who set down rules for participants in financial markets and these rules may be perceived as onerous and costly to people in the financial community, but ultimately it's their salvation and it's what makes everything possible.

政府设立监管机构,监管机构为金融市场的参与者,制定法规条令,这些规则对金融界,有着极其严格的约束,但这些规则最终使得金融界运作良好,免遭灭顶之灾

耶鲁公开课 - 金融市场课程节选

They said colonies halfway around the world would be costly to protect.

VOA: special.2010.07.22

Saving these lives does not need to be costly, and it can be done now.

FORBES: Angelina Jolie Proves Medical Care Saves Lives -- If You Can Get It

Duplicating those efforts every year would hardly be efficient and it would be costly.

FORBES: IRS Targets 100,000 Tax Professionals For Noncompliance

Even though complying with such rules can be costly, hardly anyone complains, even in private.

ECONOMIST: Chinese internet companies