上腭

• It consisted in a peculiar bird - like turn , a sort of liquid warble , produced by touching the tongue to the roof of the mouth at short intervals in the midst of the music - the reader probably remembers how to do it , if he has ever been a boy
  这声音很特别，像小鸟的叫声，一种流畅而委婉的音调。在吹这个调子的时候，舌头断断续续地抵住口腔的上腭读者若曾经也是孩子的话，也许还记得该怎样吹这种口哨。