In fact, this joint is more or less just one long bone (the femur, or thighbone) stacked on top of another long bone (the tibia, or shinbone).

• 事实上，这种关节或多或少都是一根长的骨头（股骨，或大腿骨）堆叠在另一根长的骨头（胫骨，或小腿骨）上。