homework has been finished中be是什么词助动词?系动词?请帮忙分析下

They have been doing their homework能改成：he has been doing their homework 吗?have改成了has Wang Hai has been doing homework since this morning（对doing homework提问） Three fourths of the homework ( )todaThree fourths of the homework ( )today 中间填has finished 还是 has been finished 为什么 Three-fourths of the homework [ ]today.A;has finishedB;has been finishedC;have finishedD;have been finished必须有理由 Three-fourths of the homework ______today.a.have finished b.has been finished c.has finishedThree-fourths of the homework ______today.a.have finished b.has been finished c.has finished d.have been finished Three-fourths of the homework ______today.a.have finished b.has been finished c.has finishedThree-fourths of the homework ______today.a.have finished b.has been finished c.has finished d.have been finished Three fourths of the homework has been done today 为什么不用have? “Recently he has been refusing to do his homework”中文怎么说 如题,关于had gone in & has been in 的区别HOMEWORK, homework has been finished中be是什么词助动词?系动词?请帮忙分析下 As a student ,you must (fi )the homework in time. 1.Simon has finished his homework a moment ago 2.Hong Kong's new airport has been in service since has been Your homework today hasnt been done,__?A.have you B.has it C.do you D.hasn't it 1.Mary has been a nurse for seven years否定句,疑问句,回答 2.Tom has done his homework.2.Tom has done his homework.否定句,疑问句,回答 phenomena 和phenomenon那一个是复数形式?以下是Meriiam—Webster的解释：Main Entry:phenomenaPronunciation:fi-*n*-m*-n*,-*n*Function:noun Inflected Form:plural -nas Date:1576nonstandard :PHENOMENONusage Phenomena has been in occasional u --has jack finished his homework yet?--i've no idea,but he___it this morning A.was doingB.had been doing C.has done D.did 问下被动语态问题,have been done 是现在完成时的被动语态,那we have done this homework怎么改被动?应该是This homework has been done by us,但是翻译怎么都不对啊.