A: Listen! There__________ someone __________ at the door.B: It must be your sister.
A: is; knocking
B: is; knock
C: are; knocking
D: are; knock
A: is; knocking
B: is; knock
C: are; knocking
D: are; knock
举一反三
- I heard someone _______ loudly at the door while I was listening to the radio. A: knock B: knocking C: to knock D: knocked
- Suddenly he heard someone（）gently on the window. A: knock B: knocking C: knocked D: to knock
- I was almost asleep last night when I suddenly heard someone _____ at thedoor.(2013年真题） A: be knocking B: knocking C: to knock D: having knocked
- He had three of his teeth _______ out in the fight. A: knocking B: knock C: knocked D: be knocking
- I ___________ (listen) to the music when someone __________ (knock) at the door half an hour ago.