You'll probably be able to buy supplemental insurance at an extra cost.

再多付一些钱的话，你或许就能买附加险。

《柯林斯英汉双解大词典》

Your wedding ring can be engraved with a personal inscription at no extra cost.

你的结婚戒指可以刻上个人题字不另收费。

《柯林斯英汉双解大词典》

This feature is included with the database server at no extra cost.

该特性是数据库服务器附带的，没有额外成本。

youdao

The optional, extra-cost, 4G LTE cellular-data capability made it feel like I was always on a fast Wi-Fi connection.

WSJ: The New iPad Review: Faster, Sharper and Thicker | Walt Mossberg

Also, unlike the iPad, it has an easily accessed slot for extra-cost flash memory cards that can expand its storage.

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Unlike the iPad and some Android tablets, neither Surface can be ordered with built-in cellular connectivity, though the Pro can accept extra-cost plug-in cellular modems and, like competing tablets, it can be wirelessly tethered to a cellphone or stand-alone cellular modem.

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