He has been doing这个句式是?代表什么?如何使用?请朋友解答.

He has been doing这个句式是?代表什么?如何使用?请朋友解答. 翻译句子：he has been doing nothing else ever since. They have been doing their homework能改成：he has been doing their homework 吗?have改成了has he _____ research these three years,and he ___several discoveries this year.a.has been doing ,made b.has been doing ,has made.能否说明原因？ He has been here for two weeks改同义句He has been here ( )two weeks( ) Jim has been over his homework and he is free now这句可以等于下面那句吗?帮我挑挑刺,Jim has finished doing his homework already.He is free now has been doing have been done区别 he has been married for three years 句中has been married 是被动语态么? he has been married for three years 句中has been married 是被语态么? He has been in Canada for seven years .同义句 he has already been to america 变否定句 he has been a soldier since last year同义句 He has been a soldier for 5years同义句 he has been away for three weeks.写出同义句, He has been here for two weeks改同义句 where in city he has been this 连词成句 have/has been done 是现在完成的被动语态但He has been there for six months .这个句中的has been 与前面所说的现在完成时的被动有关系吗? i has been doing 还是i have been doing