rap on the door 敲门
rap out 说出
rap about 谈论
A: Did you hear someone rapping at the door?
A：你听到有人在敲门吗？
B: Yes, I rapped back to let them know I am there.
B：是的，我也回敲了几下，让他们知道我在那儿。
1) 敲击，轻敲
2) 说唱
3) 谈论
1. 快速敲击
verb
1. to strike a surface with quick, sharp blows
Synonym: knock, tap