You can also commonly find a number of optional functions in a particular implementation of an ESB pattern.

您通常还可能在 ESB 模式的特定实现中发现一些可选功能。

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Again, these are categorized into the mandatory (functions that are always present in this business pattern) and the optional (functions that may or may not be present).

同样，这些功能也分为必需的功能(在这个业务模式中必须存在的功能)和可选的功能(可有可无的功能)两类。

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Simply connect the camera to an HDTV with an optional HDMI cable and use your HDTV's remote to control playback functions and navigate the camera's menus from the comfort of your couch.

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