three fourths of the homework have finished 怎么理解 用have finished对吗我在一个语法练习上找到的原题have finished 我不能理解 怎么把homework理解为复数？

Three-fourths of the buildings was destroyed. Three fourths of the students are from China.同义句 three fourths与three-fourth有什么不同?three-fourth of the students Three fourths of the homework ( )todaThree fourths of the homework ( )today 中间填has finished 还是 has been finished 为什么 ( )of the world's books and newspapers are written in English A.Three quarterB.Three of quarters C.Third fourths D.Three fourths 请说明理由 three-fourths of the surface of the earth ( ) seaA isB are three-fourths of the surface of the earth ( ) sea 是is 还是are? Nearly three fourths of the earth做主语时,谓语用单还是复啊? Three fourths of the homework has been done today 为什么不用have? 英语中three fourths of the materials 用单数还是复数? Three fourths of the land____ with trees.A.are covered B.is covered 选那一个 Three fourths of the population of china are farmers.这句话的主语是不是;the population of the china? I think three fourths of the materials I listened to at the beginning of the exam are easy.意思 ---I think ___of the materials I listened to at the begining of the exam ___easyA.three fourths;is B.third four;are C.three fourths;are D.three fourth;arethree 什么情况下用is are? three-fourths of the informationg about the 2008 Olympic Games ______ downloaded.three-fourths of the informationg about the 2008 Olympic Games ______ downloaded from the Internet.此处写are还是is a.Three fourths of the teachers present _____ againstthe plan.b.Three fourths of the surface of the earth ______covered with water.A.is B.are C.was D.were为什么分别选B、A? A number of books ____kepts in the reading-room and ___of the students'time___spent there.A.are,threee-fourth,is B.is,three-fourths,areC.are,three-fourths,is D.is,three-dourth,is I think _____of the materials llistened to at the beginning of the exam____easy. A.three fourths...I think _____of the materials llistened to at the beginning of the exam____easy.A.three fourths;isB.third four;areC.three fourths;areD.three fourth;are