sheep的复数是sheep。
n. 羊，绵羊；胆小鬼

例句：
Kangaroos compete with sheep and cattle for sparse supplies of food and water. 

袋鼠与绵羊和牛争夺为数不多的食物和水的供应。

Competitors have six minutes to shear four sheep. 

参赛者们有6分钟的时间来给4只羊剪毛。

Sheep were grazing in the fields. 

羊在野地里吃草。

They kept a small flock of sheep. 

他们养了一小群绵羊。

The field had been grazed by sheep. 

这块地羊已经啃过了。