The consonants in babble mean the baby is practicing, shaping different sounds by learning to maneuver the mouth and tongue, and listening to the results.

婴儿咿呀学语时发出的辅音字母就是他们在练习的过程，是他们摆好嘴巴和舌头形状发声的过程，也是他们听自己发音的过程。

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A four-day-old baby can distinguish the speech patterns of its native tongue from a foreign language.

一个出生仅四天的婴儿就能分清母语和外语的讲话模式。

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Baby snake: I just bit my tongue!

小蛇：我刚咬了我舌头！

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Stick your face right up to the newborn baby and go like this and stick your tongue out.

把你的脸凑到婴儿的面前,像这样对婴儿做鬼脸,把你的舌头伸出来

耶鲁公开课 - 心理学导论课程节选