膝關節連接大腿和小腿，由兩個關節組成：一個在大腿骨和小腿骨之間，另一個在大腿骨和膝蓋骨之間。
The knee joint connects the thigh and the shank and consists of two joints: one between the thigh bone and the shank bone, and the other between the thigh bone and the kneecap.
