请描述航空母舰的两种用途。

Please describe two uses of an aircraft carrier.

youdao

数字证书有两种用途：建立所有者的身份，以及让所有者公钥可用。

A digital certificate serves two purposes: it establishes the owner's identity, and it makes the owner's public key available.

youdao

在单一环境中使用两种功能，该服务只能使用一次，因为它们都是为特定的用途设计的。

With both functions in a single environment, the service could be used only once, for the specific purpose it was designed for.

youdao