He has an endearing habit of licking his lips when he's nervous.

他有个紧张时舔嘴唇的可爱习惯。

《柯林斯英汉双解大词典》

Road is still very far away, when Klaette unable to cope to the ground, the cat will come over, licking his lips, cheeks, pulling his hair, had to encourage him to stand up, move on.

路还是很远，每当科莱特支持不住摔倒在地时，小猫都会走过来，舔他的嘴唇、脸颊，拉扯他的头发，鼓励他不得不重新站起来，继续前行。

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Some of the most cutting things Peters had to say focused on House Speaker John Boehner, whose apparent indifference toward the State of the Union -- scowling, licking his lips, looking very "get me outta here" -- made her angry.

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Sheens was critical of his side's defence and said New Zealand would be "licking their lips" ahead of their meeting next week.

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