She spent time in front of a mirror, retraining the shape of her mouth, forcing her lips into a long oval "O" to evoke Ms. Garland's face in midbelt but pulling back when the look turned clownish.

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Over the years the word had moulded itself to the shape of an African mouth.

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The mouth is often in an "O" shape from shock.

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There is also the "vocal tract" - everything upwards of the larynx along with the mouth, which are well known in humans to shape sung notes and subtle vowel sounds.

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