First, read the English article below.

This exercise helps to strengthen and tighten the muscles in your face and neck. To do it, stand with your back and neck straight. Raise your chin toward the ceiling and look at the ceiling. Pucker your lips toward the ceiling and hold for a count of 10 seconds. Repeat 10 times. Do the exercise every day for best effect. Stand with your spine upright. Turn your head to the side so that your chin is parallel to your shoulder. Your eyes should be looking off to the side, too. Slowly roll your head downward, then up to the other side. Repeat 10 times. This is the muscle that runs down your neck from your jaw. Stand with your neck erect. Tighten the tendons in your jaw by pulling your lips up over your teeth and turning the corners of your mouth downward, almost as if you were frowning. Hold for 10 seconds, then relax. Repeat the exercise ten times. Place it against your neck and hold it there with your chin. Press your chin against the ball tightly, then slightly release. Repeat ten times. This is an easy exercise to do, since it hardly requires any thought. Chewing gum keeps your jaw muscles strong, helping to reduce a double chin. 

Now, please write a short abstract for it in Vietnamese. Abstract:
Tập nâng cằm nhiều lần. Xoay cổ. Tập với cơ cổ dưới hàm. Bài tập với banh tennis. Nhai kẹo.