Cactus lives in a dry desert, and its leaves become thorns. By reducing the evaporation surface area, water evaporation is greatly reduced. Most cacti grow in a dry environment. Some are cylindrical, 10 meters high and weigh about 20000 kilograms. They stand tall and spectacular. Some prickly cacti, some of which live for more than 500 years, can grow into giant balls with a diameter of two or three meters. People cut the upper part of it and dig soft and juicy stem meat to quench their thirst. Cactus also has a special ability. In the dry season, it can go into a dormant state without eating or drinking, minimizing the consumption of nutrients and water in the body.