bird的復(fù)數(shù)形式怎么寫(xiě)

　　例句：

　　1、This species of bird is decreasing in numbers every year.

　　這種鳥(niǎo)的數(shù)量在逐年減少。

　　2、 The area has a wealth of bird life.

　　這個(gè)地區(qū)棲息著大量的鳥(niǎo)。

　　3、The lake is noted as a home to many birds.

　　這個(gè)湖作為許多鳥(niǎo)類的棲息地而聞名。

　　4、Huge numbers of birds had flocked together by the lake.

　　成群的鳥(niǎo)聚集在湖邊。

　　5、 The male and female birds take turns in sitting on the eggs.

　　雄鳥(niǎo)和雌鳥(niǎo)輪流伏窩。