cow which produces milk

例句：

1. 1. The farmer milked the cow every morning.
   农夫每天早上挤牛奶。
2. 2. She fed the cow with hay and grain.
   她用干草和谷物喂养牛。
3. 3. Cows are essential for dairy production.
   奶牛对于乳制品生产至关重要。