bull kept for covering

例句：

1. 1. The bull is the largest male member of the herd.
   公牛是牛群中最大的雄性成员。
2. 2. The bull was so strong that he could lift a car with his horns.
   公牛非常强壮，他的角可以抬起一辆汽车。
3. 3. Bulls are often used in agriculture to help with plowing and planting.
   公牛常用于农业，帮助耕地和播种。