bird是可数名词还是不可数名词?

The bird disappeared into the scrub.

鸟消失在矮树丛中。

The bird flapped its wings furiously.

那只鸟使劲地拍打着翅膀。

There was a bird perched on the roof.

有一只鸟落在屋顶上。

A bird had pecked a hole in the sack.

一只鸟把袋子啄了个洞。

The bird fanned out its tail feathers.

这只鸟把尾羽展成扇形。

The bird caught the insects in mid-air.

鸟在半空中捕捉了昆虫。