Do not allow a simple CD check for the old version.

千万不要去检查旧版本是不是真的升级了。

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After looking at some simple CD examples, the article explains what is meant by the absolute path and the relative path and when to use each one.

本文首先展示一些简单的cd示例，然后解释什么是绝对路径和相对路径，以及何时使用它们。

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To get online help, you also need to order an inexpensive CD, which is small (~ 10mb) and simple.

如需联机帮助，您还需要定购一张便宜的CD，它容量较小(大约10mb)，而且简单。

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Copying them onto a computer file -- also known as 'ripping' a CD -- is simple.

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The deck sections roughly mirror most of the controls that you might find on a good CD turntable, and the mixer is a simple two-channel affair that lets you blend tracks between them.

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It should be a simple upgrade in manufacturing technology to go from manufacturing the current CD to making the Double Density CD.

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