Laughter is one of the most infectious expressions of emotion.

笑是最具感染力的情感表达方式之一。

the rights of the individual to freedom of expression.

个人言论自由权。

Levin sat there, an expression of sadness on his face.

莱文坐在那里，神情忧伤。

I think I put more expression into my lyrics than a lot of other singers do.

我认为我在唱歌时比许多其他歌手注入更多的情感。

She spoke in a quiet voice but used remarkably coarse expressions.

她说话声音很轻，但用词粗俗。