it is four years since I joined the army.这里的is,为什么不用was呢?

It is four years _____ I _____ here. it is four years since I joined the army.这里的is,为什么不用was呢? 分析一下它的含义?It is has been four years since he lived here． It is nearly four thousand years _____A.youngB.oldC.longD.far It is four years since he bought the car.同义句 it is said that ___umbrella was invented over four thousand years ago by chi it is said that an umbrella was inventedover four thousand years ago by chinese people It is four years since I joined the army.啥意思 Wen Qing has been making kits since four years ago(同义句）It is four years ________ Wen Qing _____ to make kites It is 1965.A little boy is at the beach with his ( ) .He is four years oldPlease看清题目捏 ... He is only four years old.是什么意思? four years Four Years 初中英语同意句转换?He has been making kites since two tears ago.It is four years _______he_______to make kites. (it is ） four years since we last saw each other.这句话括号里为什么不是there were it is four years since i an english teachera become b became c becomes d have became说下为什么 下面两个句子有什么区别?It is four years since I knew Candy.It has been four years since I knew Candy这两个句子有什么区别? It is said that ____umbrella was invented over four thousand years ago by ChIt is said that ____umbrella was invented over four thousand years ago by Chinese people.A.a B.an C.the D.不填