Fake smiles only involve the mouth and lips. It's easy to distinguish between the two.

伪装出来的笑容只反映在嘴角和嘴唇上，二者很容易区分。

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And as he looked at the unpractised mouth and lips, he thought that such a daughter of the soil could only have caught up the sentiment by rote.

在他看着她那张纯真自然的嘴和嘴唇的时候，心想，这样一个乡下女孩子会有这种情绪，只不过是照着别人的话说罢了。

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Ben took his beer-mug from his mouth and wiped his lips with the back of his hand.

本把啤酒杯从嘴边拿开，用他的手背擦了擦嘴唇。

youdao

The jury heard that Booth and her partner were awoken by a loud thud at about 12.40 GMT to find Aaron lying down with a brown mouth and lips.

BBC: Lauren Booth

Compressed lips, licking lips, hand covering mouth and rubbing upper lip.

FORBES: Why Lance Armstrong Looks Like a Liar

As soon as he held it in his hand, he put the instrument's mouth to his lips, like a thirsty person grabbing at a bottle of water and pressing it to his mouth.

NPR: 'A Tale of Music': From 'Literature from the Axis of Evil'