Cattle feed on grass.

牛以草为食。

youdao

For instance, several kinds of birds feed on insects flushed out of the grass by grazing cattle.

例如，几种鸟类以被放牧牛驱赶的昆虫为食。

youdao

Farm animals can also pollute water supplies. Animals like cattle, pigs, sheep and goats are often left to feed on grass in open fields bordered by streams or rivers.

农田动物也会污染水源。牛，猪，绵羊和山羊等动物通常在小溪或河边的广阔的草地上放牧。

youdao

Ranchers had planned on using the grass to feed cattle... and the fires also destroyed miles of fences that keep the cattle in.

NPR: Fires Scorch Nebraska Cattle Industry