So, initially they came up with four lines and then eventually five and even six, and then they went back to five by the fifteenth century.

那么,他们最初提出的是四条线,但是最终却是五条线,甚至六条线,然后在十五世纪又回到了五条线

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Tests show in the nineteenth century that people could type four or five times as fast as they could handwrite and there's no ambiguity because it's very clear what key was struck; whereas, handwritten--fast handwriting becomes impossible to read--or difficult.

通过测试显示，在19世纪,人们打字的速度是手写的4至5倍,而且也不存在字迹模糊的问题,因为键盘敲击出来的非常清晰;,而手写，尤其是快速手写根本无法阅读,或者说是很难阅读。

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