The "still bird" in the poem refers to a bird that can make an elegant song.
Because the "wandering bird" referred to by ancient literati in poetry changed slightly according to the situation of poetry.
Ancient literati seemed to write about birds, but in fact they expressed their feelings by holding things. Use birds to express inner anguish or to express nostalgia for the past.
Bird characteristics
The basic structure of bird body adapts to Yu Feixiang: the forelimbs of birds have never been used for walking, but they have evolved into wings; Most of their bones are hollow; The appearance is assembly line, forming a shuttle shape as a whole; Its beak is in front, which can spread the air when flying; The pectoral muscles are particularly developed, and the wings can be flapped vigorously; A flat tail is like a rudder.