There does seem to be a tiny bit of unused space below the bottom row of keys but this seems to be necessary to permit the slider to merge into the main body.

底部按键下方有一段无用区域，这是将滑动块融入机身所必需的。

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The preface begins, "Heaven was once broken and when it was mended, a bit was left unused, and this became the famous jade of Chia Pao Yü."

小说的引子写道：很久以前，天破了一个大口，（女娲）修补（缺口）时，剩下一小块（石头），于是成了贾宝玉的那块名玉。

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