Подбор синонимов:
hard3, work3, best1, children1, chosen1, themselves1, classroom1, ideas1, finished1, men1, see1, still1, think1, digging1, like1- be hard at work
усердно работать I see the men are still hard at work - when do you think the digging will be finished? I like the classroom best when all the children are hard at work on ideas that they have chosen themselves.