Turn-out is the one of the most important skills in ballet. However, not all dancers can make it. The reason can be found in the the times when you were babies. The primitive exercises during 0-year old develop humans’ body structures and motion. Especially, quadrupped crawling develops the motion of hip joint. Without doing quadrupped crawling enough, the range of motion of hip joint can not developed enough to make a perfect turn-out. It can not be compensated by doing any training after grew up. The only way to compensate that insufficiency is to redo quadrupped crawling. Naturalization exercises promise us recover our natural bodies and motions.