I heard someone _______ loudly at the door while I was listening to the radio.
A: knock
B: knocking
C: to knock
D: knocked
A: knock
B: knocking
C: to knock
D: knocked
举一反三
- I heard someone _______ loudly at the door while I was listening to the radio.
- 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
- 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
- I ___________ (listen) to the music when someone __________ (knock) at the door half an hour ago.