A written language is the representation of a spoken orgestural<span> language by means of a writing system. Written language is an invention in that it must be taught to children, who will pick up spoken language (</span>oral<span> or sign) by exposure even if they are not specifically taught.
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I think the first or the second phrase works the best
I'll go to the Rockies but I'm afraid of heights.
Usually, you don't put a comma before "but".
