Frogs are cold-blooded animals. If the temperature is too low, they will freeze to death, hibernate in winter, and resume their activities when the temperature gets warmer the next spring. Frogs belong to chordates, amphibians, Anura and Ranidae. Adults are tailless, eggs are laid in water, fertilized in vitro, hatched into tadpoles, and breathed through gills. After the mutation, adults mainly breathe through the lungs and skin. The upper jaw has teeth, usually plow teeth. Shoulder straps fix the chest, the vertebral body is uneven, and the transverse process of sacrum is columnar; There is no mesenchymal cartilage between the two joints at the toe. The eardrum is obviously hidden under the skin, and the skin is smooth or warty. Tongue is generally oval, and there are many notches at the back end.