must have working hard与must have been working hard的区别

must have working hard与must have been working hard的区别 Mary ___on her new priject late last night ,so she felt sleeply in the office this morninga.must work b.must have been working c.must be working d.must have been worked选什么. he （） tired now after working for ten hours have to need must would The elder brother must know,ha ha,sister you must have the boy are sweeting all over.they must have been working 这句话怎么翻译,为什么用完成进行时 he didn't come yesterday,he ______busy working in the lab怎么选must have been?.3Q if i had six oranges in one hand and seven applesin the other,what must i ha急If I had six oranges in one hand and seven apples in the other,what must I have?翻译并回答～ have been working 是什么时态 must have been done must have done must have/ must have been的区别 You ( )be tired .you have only been working for an hour.A.must B.wont C.cant D.may not If you keep working hard and make more progress,you ____ have an opportunity to travel during the summer holiday.A shall B must C need D dare 25.He got up so late in the morning so he ___________ working late at night.A.could have been B.must have been C.should have been D.would have been must,have to,have got must／have to造句 must have to区别 must not have