Housed within the system unit, a sound card contains connectors that project from the back of the computer so that you can attach speakers, headphones, and a microphone.
声卡安装在系统机箱内，它在计算机后面有一些突出的接口，可供用户将扬声器、耳机和麦克风插在上面。
2
My test unit also came with an odd little add-on microphone poking out from the bottom, even though it had a built-in mic at the top.
我测试的这台电脑还有一个古怪的外置麦克风，从机器底部伸出来，而其实电脑顶部已经有了一个内置麦克风。
3
The microphone is quite sensitive so you can be some distance from the base unit and still be heard by the call centre staff.