英语单词 hard-working(勤勉的,努力工作的) 中间的“-”符号表示的什么啊?

英语单词 hard-working(勤勉的,努力工作的) 中间的“-”符号表示的什么啊? working hard! hard-working Working hard. Playing hard. 是什么意思 hard-working、hard working、working hard 区别.hard-working是名词吗? hard-working的反义词 hard-working怎么读 hard-working比较级,最高级 hard working怎么读 hard-working什么意思 hard-working什么意思 working hard and keeping 英语翻译as hard-working 用hard-working造句 He is working hard people 对working work hard和hard working的不同 hard-working 和work hard的区别 hard-working与work-hard的区别