1.Charlotte rapped on the window with her knuckles.
夏洛特用指节轻敲着窗。
2.Our fingers bend at the knuckle.
的手指在指节处弯曲。
3.He got a rap over the knuckles for spending too much money on his business lunches.
因为在商务午餐花钱太多,他挨了一顿批评。
4.The most common type of joint in the human body is the diarthrodial joint -- knuckles and shoulders are examples -- in which two bones come together in a capsule.