The card was advertised as being safer than carrying cash and more convenient to only pay once a month.

广告宣称一卡在手比带现金来得安全，而且月付的缴费方式更提高了其便利性。

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But the dress New Style Flower Girl Dresses is worth while to invest in, to pay a lot if we take into consideration the fact that you wear it once in life time, only one night?

但是如果邀请穿着新颖的花童的话会是一笔不小的开销，事实上你一生只穿一次，有且只有一次对吧？

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Don't forget to add in the things that you only pay once a year like your TV license or your car insurance.

BBC: Pile of coins

It puts in place mechanisms to make sure that we only pay once for each service and that each service we pay for is covered in a legitimate charge.

WHITEHOUSE: Press Briefing on the President's Budget

Major publishers are taking wildly different approaches to resolving the woes surrounding e-book lending at libraries: they're experimenting with both the short-yet-cheap subscription as well as an expensive option to pay only once for perpetual use.

ENGADGET: Macmillan tests selling e-books to libraries in two-year stretches