If it is difficult to state definitely one or several ports, optional ports can be adopted.

假如难以明确写出一个或几个港口，就可以采用选择港这个办法。

youdao

Any of the eight ports can be configured as internal, external or optional.

任何端口均可配置为内部端口、外部端口或选配。

youdao

Lockable doors, desktop power, data ports, and a scalable power supply are optional features.

任选项包括可锁门，台式电源，数据端口，和可扩展电源。

youdao

The hardware includes an optional pen and lots of standard ports, all of which the iPad eschews.

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Now available with Toshiba's stylish Fusion finish, a large touch pad with gesture support, plus optional HDMI and USB 3.0 ports, the laptops are a great choice for those looking for the essentials to tackle basic tasks at an affordable price.

ENGADGET: Toshiba updates its all-in-ones, mainstream Satellite laptops for early 2013

The tablet will also have an optional dock that includes a traditional phone and USB ports.

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