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1、國際愛牙日的簡介：In 1989, the ministry of health, education and other ministries and commissions jointly signed, the annual September 20 as the National Day of loving teeth. The aim is to mobilize the power of the society to prevent and protect dental diseases and popularize dental knowledge among the public through tooth day activities, enhance oral health concept and self-awareness of oral health, and establish oral health behavior, so as to improve the oral health level of the whole nation.（1989年，由衛(wèi)生部、教委等部委聯(lián)合簽署，確定每年的9月20日為全國愛牙日。宗旨是通過愛牙日活動，廣泛動員社會的力量，在群眾中進行牙病預(yù)防、保護牙齒知識的普及教育，增強口腔健康觀念和自我口腔保健的意識，建立口腔保健行為，從而提高全民族的口腔健康水平。）

2、牙齒的重要性：The teeth are a marvel. They break up all your food over the course of your life, while being strong enough to withstand breakage themselves.牙齒是個奇跡。你一輩子都要靠它們來把你所吃的食物咬碎，而且它們本身還要夠強健，才能禁得起這么長久地磨損。