Users can buy refill card at retail and add credit to the pre-paid account.

用户可以购买充值卡，给预付费账号充值。

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A villager, working hundreds of miles away from home, buys a cell-phone refill card with his earnings.

一位在离家几百英里远的地方工作的村民用自己的收入买了一张手机充值卡。 他打电话给接线员来把钱邮回家里，接线员用这张卡给电话充值。

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Refill your card to use the balance.

你可以往卡上充值以使用卡上的结余。

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If a card dips below a minimum dollar value, Starbucks will automatically refill it from your credit card or debit bank account.

FORBES: The Overachievers: Starbucks Delivers

Google will also offer its own prepaid card, but it requires a credit card to setup and refill.

CNN: Mark Milian

Adding to monthly balances is accomplished by buying Refill cards or by registering a credit or debit card or PayPal account online at CommonCentsMobile.com.

ENGADGET: Common Cents Mobile becomes Sprint's latest prepaid brand, exclusive to Walmart