Cracks in the middle of the tongue have the following causes: 1, deep cracks in the tongue are usually more serious, atrophic lesions of the tongue make the epithelial layer of the tongue lose its normal structure, some of the papillae become flat and fused, and some of them will atrophy and fracture and form cracks, under which thickened scar contraction can be seen; 2, if the tongue is cracked with fluid, it is usually considered to be caused by qi deficiency, modern medical research suggests that cracks in the tongue Mainly because of atrophy of the tongue mucosa, so that the longitudinal or transverse lines of the tongue penetrate the surface and form; 3, cracked tongue refers to the cracked tongue, also refers to the cracked tongue moss, in the identification of the evidence should be identified from the sweet and moist tongue, a number of and cracked belongs to the external disease, dry heat is more serious, this time should nourish yin, benefit qi and generate fluid, replenish yin and fire, clear heat and moisten dryness. If heat is more prevalent, a red-red tongue with cracks can appear, and if blood deficiency is not moistened, a pale white tongue with cracks can appear. Spleen deficiency is manifested by a white, pale, fat tongue with teeth marks on the sides, which can also appear as cracks.