是work hard at sth.还是work hard on sth.

是work hard at sth.还是work hard on sth. work hard in还是work hard at? 是work hard at English 还是on English?为什么 work hard at hard 是hard to do sth 还是 hard doing sth 是they work all hard还是they all work hard 英译汉:work hard at work hard at中文 用keep还是keeping?记住老师的话,好好学习.the teacher’s words and work hard答案是keep sth.in mind或Know sth.by herat All the chilldren work hard at还是work hard on our lessons Work hard at my study还是on my study? work hard in 还是work hard on 英语提问,紧急!是work hard ,还是work hardly? I was hard at work on a term paper有语法错误吗?...hard at work on ...work为什么没有ing呢……还是说答案是错误的呢…… work hard at your lesson还是on your lessonwork hard at your lesson还是on your lesson 还是都可以? I think I should work ____(hard) at English填hard还是harder?为什么 work hard at English是什么意思 I work hard at school.