就是说A问：There is someone koncking at the door.Who is that?

——Oh,someone is koncking at the door. —There is a knock at the door.—---------------?A.who is that someone is knocking at the door,who is it? A this is a polic ----Someone is at the door.----_______?A.what is it B.who is --who's that at the door?--____ is a postman. Who is that at the door? Who is that at the door ？ 有人敲门,会是谁呢 There is someone _________ at the door .Who ____it 6.There is someone knocking at the door,who _____ it be? (It is)(There is) someone at the door. someone is knocking at the door （）i go and see who it is A s someone is knocking at the door .（）i go and see who it is A