cattle 牛（复数）
male cattle
=bull 公牛
female cattle=
cow 母牛
three
cattle三头牛
some cattle
一些牛
one cow /one
bull 一头牛(不能用cattle)
beef : meat
from a cow肉牛的肉。 牛肉
calf :a young
cow ,小牛/牛犊
Each cow
normally produces only one calf at a time
通常情况下，一只母牛一次产一只小牛
the newborn
calf fears no tiger 初生牛犊不怕虎
ox: 干重活的a bull
that has been castrated ：（阉割的）公牛
steer : a bull
that has been castrated ：（阉割的）公牛
bull : the male
animal in the cow family 公牛(通常未阉割的)
cow:母牛/奶牛/肉牛/菜牛
buffalo水牛.asian
buffalo和african buffalo亚洲水牛和非洲水牛
cattle是集合名词，不能加不定冠词a，
用作主语时，句子的谓语动词多用复数。
a herd of
cattle 一群牛
The cattle
usually graze in the grass land.
牛通常在草地吃草.