The most common hand posture is palm hand, and there is a familiar mouth hand that looks like a peacock's head, and there is another mouth hand with thumb up, forefinger bent and other fingers tilted. This hand shape is not very common, it is probably three bends of the hand. In the three bends, the requirements for the waist are stricter. In fact, the best way to show your waist is to tilt your hips as much as possible, and then your chest and waist will naturally show up.