wheel horse

wheel-horse的词性：
n.（名词）

1. The horse in a team that follows the leader and is harnessed nearest the front wheels.
辕马：一列马中跟着领头马并与轮子套得最近的那匹马

2. A diligent, dependable worker, especially in a political organization.
实干家：工作勤奋、值得信任依赖的人，尤其指在政治组织中