It had a sense of “mental impairment” that evolved not only into these two meanings of dumb, but into the word deaf as well.

它有“智力损伤”的意思，不仅衍生到dumb的这两层意思，还衍生到了deaf这个词。

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And some of the research in our center has shown that when deaf readers read an English word, it activates their sign representations of those words.

并且我们研究所的一些研究也表明，当一个耳聪的人在读一个英语词语的时候，会激起他们对这个词语的手势表达。

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