bird of passage

You can't find him, he is a bird of passage.

你打找不到他，他是一行踪不定的人。

with a voice that told of home ， like the voice that is heard by the bird of passage.

它的声音像画眉那样清脆，像人心那样充满了活力。远方飞回的候鸟听着它，像是听到了故国的歌曲。

Andrew left for Madrid again yesterday-he's a regular bird of passage.

安德鲁昨天又动身到马德里去了，他真是个行踪不定的人。

He was a bird of passage until he married and bought a house.

他漂泊无定,直到结了婚,买了房子才安定下来.

I'm a bird of passage, dah-ling, just flitting through.

亲爱的，我是只飞来飞去信使鸟，为的就是完成这些。

He is a wanderer on the face of the earth. I'm not a bird of passage.

我不是漂泊不定的人。

Which one of the birds is the bird of passage?

这些鸟中哪只是候鸟?