Black Friday: lifetime access is on a special offer in the app, until November 30. Black Friday: special offer on lifetime access, until November 30. Download
괄약근은 소변과 대변을 조절하는 역할을 합니다.gwal-yakgeun-eun sobyeon-gwa daebyeon-eul jojeolhaneun yeogaleul hamnida.The sphincter plays a role in controlling urine and feces.