可以单独用，或者用它做隐性的妆前霜。

Perfect alone or as an invisible under-makeup primer.

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每个密匙值都可以单独用于加密消息，但是不能用于解密由它本身加密的消息。

Each key value can be used separately to encrypt messages, but it cannot be used to decrypt the messages it was used to encrypt.

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生物柴油是以菜油或是植物油加工而成的燃油。可以单独用于柴油机，也可以和以石油为基础的燃油混合使用。

Biodiesel is made from processed vegetable or plant oil, and can be used in diesel engines on its own, or blended with petroleum-based fuel.

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