repress an emotion; stifle laughter or a retort
咬紧嘴唇；压抑感情；抑制笑容；忍住不说
she bit her lip to stop the rush of bitter words.
她咬紧嘴唇，强忍住没冲口说出尖刻的话。
raise a corner of one's upper lip to show contempt; sneer
（表示轻蔑的）撇嘴
look forward to something with relish; show one's satisfaction
舐嘴唇（表示满意和渴望）
be eaten, drunk, or spoken
吃进去；喝下去；说出口
express approval of or support for (something) without taking any significant action
口惠而实不至