three years has/have passed选哪个?语法书上写：年份看做整体用单数动词可有人说复数

Tom has( )for three years Three years has past.为什么“three years”可以看做单数? Three years have/has passed.有谁给个明确的答案,到底是have 还是has Three years -- since they came to this schoolA .have past B.has passed C .has past D .have passed nearly three years ( )has passed 还是 have past since i studied at this middle school three years （ ）passed,we graduation from the school.1.has 2.have The Whites _(has/have)been in china for three years?应该选哪个答案,为什么? I [ ] English for three years 1.learn 2.learned 3.have learned 4.has learned Three years has passed since the students came to this school.保持愿意The students have ( )( )this school for three years. three years have passed since they met last time.为什么不是has passed ?表示时间的不是用单数吗? three years has/have passed选哪个?语法书上写：年份看做整体用单数动词可有人说复数 Great changes ________ in the last three years in our city .A.has happened B.has take placeC.have happenedD.have take place 呵呵是抄错题了 My parents have been to New Zealand for three years.改错Her uncle has started to work for nearly 9 years.改错 顺便说下 she has three books 还是she have three books The Smiths has been in China for three years.The Smiths ______ China for three years.A.have come答案是选C,可这不是三单吗,不应该选D吗? his mother died .she has been_____for three years Mr Green has been in Beijing since three years ago. Tom has-- for three years Agone Bbeen away Cleft Dcome