Corns and calluses
Overview Corns and calluses are thick, hardened layers of skin that develop when your skin tries to protect itself against friction and pressure. They most often develop on the feet…
VOA英语教学网 - VOA LEARNING ENGLISH
一个让你免费在线学习VOA英语的好地方! 无须报名, 不收学费, 全年无休, 保证提高! (^_^)
Overview Corns and calluses are thick, hardened layers of skin that develop when your skin tries to protect itself against friction and pressure. They most often develop on the feet…