union stud

例句：

1. 1. The farmer used a union stud to cut the wheat.
   农民使用联合收割机割小麦。
2. 2.The union stud was designed for large-scale farming operations.
   联合收割机是为大规模农业操作设计的。
3. 3. The union stud has become an essential tool in modern agriculture.
   联合收割机已成为现代农业中不可或缺的工具。