1·Dolphins lack vocal cords, nevertheless creating sounds: a complicated system of whistles, squeaks, moans, trills, and clicks are produced by sphincter muscles inside the blowhole.
海豚没有声带，但却能发声：一个由口哨声、吱吱声、呻吟声、颤音和咔嚓声组成的复杂系统是由喷水孔内的括约肌产生的。
2·Donald runs through an impressive repertoire of bird and tree frog trills, then hops down to his mossy mat.
唐纳德真令人刮目相看！他演唱一支鸟类的鸣叫和树蛙的颤音相结合的曲调，作为压轴戏，然后从树上跳下，落到他的青苔的草坪上。
3·At the thought the minor movement of the Beethoven begins to play in her head, the trills long and terrible like little rolling drums.
一想到这，贝多芬的小调乐章就开始在她脑海里演奏起来，悠长而又可怕的颤音，像是轻轻擂出的鼓点- - - - - -。
4·Mutual respect… she laughs and trills and she sings when she speaks.
她的笑声带着颤音，说话像在唱歌。