additional fee

基本解释

The company pays an additional fee to its e-mail provider to archive e-mails. That way, there is no question of whether to keep or delete e-mails.
他們公司還額外付費給電子郵件服務提供商進行郵件存档，這樣就不存在是否保畱電子郵件的問題。
However, it should be noted that the vendors may implement the features in their next versions or for an additional fee if the requirements are stated.
然而，應該注意到，如果有需求，廠商會在其下一個版本實現這些特性，不過可能要額外收費。
Recently, airlines have received lots of attention for moving longtime standards - baggage, food, drinks, even pillows and blankets - from the "included" pile into the "for an additional fee" pile.
最近，航空公司將長期以來的標準服務——行李托運、餐食、飲品、甚至枕頭和毯子——從“機票費用已含”的一類歸入“額外收費”的一類，因而廣受關注。

Instead, they are charged an additional fee for every additional chunk of data that they use.
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Verizon Wireless asserted that third-party tethering applications could enable its customers to tether without paying an additional fee.
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It claims, for an additional fee, to be able to put together a portfolio of the best hedge-fund managers.
ECONOMIST: Buttonwood