Tearing is mainly due to fatigue and blockage of the tear ducts, prolonged fatigue of the eyes, eye transients reduce tear evaporation too fast, the conjunctival epithelium of the eye is dry and irritates the nerves, forming irritation increased tearing, the conjunctival sac is moistened as the body’s self-protective response. Tearing represents conjunctival irritation, which requires timely reduction of eye use, together with the use of warm towels for external application to ease blood circulation around the eyes, which can relieve visual fatigue and reduce tearing symptoms. In addition, blockage of the lacrimal duct is also a common cause of watery eyes. Under normal circumstances, tears secreted by the eyes can be discharged through the tear dots into the nasolacrimal duct. If the lacrimal duct is blocked or narrowed, the tears overflow out of the conjunctival sac to form a tear overflow.