为什么是is knocking：Who is knocking(knock) at the door?it's me.

为什么是is knocking：Who is knocking(knock) at the door?it's me. Someone is knocking at the door,but who can____ be? 单句改错 who is the men knocking at the door who is knocking on the door ___must be Helen. 关于it的用法1:Someone is knocking at the door .Go and see_____.为什么选：who it is 而不是who is it 4:--why don't we take a little break?----Didn't we just have ___?为什么是用one 不用it? who is knocking at the door?A.This is me knockingB.It's me. who is knocking at the door?it is ()me还是i呢?求理由 someone is knocking at the door.who [ ]it be?A;mustB;canCmayD;shall必须有理由 There is__(nobody,somebody.anybody,everybody)knocking at the door,Go and see who it is someone is knocking on the door.who can____ beA that Bthis Cthe Dit who is knocking at the door?i suppose------must be bob.A.the one B.it C.who D.he When someone is knocking at the door,you may ask______?A.Who are you B.Who it is C.What are you D.Who is it 为什么是 Who is you English teacher 而不是Who is your English teacher 为什么是WHO IS the most BEAUTIFUL OF ALL Who is the owner of the watch为什么是陈述句 请看下面的句子：Who is knocking at the door?I think (it) is Li Lei.为什么要用it? Someone is knocking at the door,but who can____ be?A.one B.he C.she D.it 6.There is someone knocking at the door,who _____ it be?A.can B.may C.must D.need