鳥是可數名詞還是不可數名詞

　　The area has a wealth of bird life.

　　這個地區棲息著大量的鳥。

　　The bird had escaped from captivity.

　　那只鳥已經逃離樊籠。

　　The bird disappeared into the scrub.

　　鳥消失在矮樹叢中。