名詞 workhorse:

1. machine that performs dependably under heavy use
2. a horse used for plowing and hauling and other heavy labor

work.horse

n.（名詞）
Something, such as a machine, that performs dependably under heavy or prolonged use:
重負(fù)荷機(jī)器：某物，比如機(jī)器，在過強(qiáng)或延長的作用下運(yùn)行得很可靠：
例句：
.the 50-year-old DC-3 . . . one of aviation`s most effective workhorses.(Christian Science Monitor)
.五十年的DC—3…航空的最有效率的機(jī)器之一.(基督教科學(xué)箴言報(bào))

A horse that is used for labor rather than for racing or riding.
役馬：不用于比賽或乘騎而用于勞作的馬
Informal A person who works tirelessly, especially at difficult or time-consuming tasks.
【非正式用語】 吃苦耐勞的人：不知疲倦地工作的人，尤指在困難的或消耗時(shí)間的工作上