How is milk produced from grass?

Walt: Add detail to the end of sentences.

Cows eat 70 kilograms of grass a day, so they can make milk and it is also healthy for them to eat. For the cwo's it is the only thing they can eat.

Also they can eat 70 kilograms of grass a day because they have four stomachs.

Cows have four stomachs, because   when the cow’s eat the grass. First it goes into two stomach first. But when the grass goes into the stomach, it breaks into little pieces. When it breaks into little pieces, it goes into the last two stomachs.