附註：阿公現在和阿嬤在中國大陸和台灣旅行，所以英文的部分等以後再補給你。

Dear Nathan:

How are you? A few days ago, grandpa saw that one of your lower front teeth had fallen, and I wanted to say congratulation to you. Children start to lose their teeth when they are five or six years old, and they develop new permanent teeth. This means that you are growing up. It’s a very cheerful thing to embark on such a new stage!

From the time you were born to the time when you are almost six years old, a total of twenty baby teeth have grown. Now the new teeth are coming out from under the old teeth, and the old teeth will loosen and fall. The new teeth are called "permanent teeth." Permanent teeth can only grow once and will not fall again. Before you are 13 years old, you will grow a total of 28 permanent teeth. Then between the ages of 16 and 19, the last four wisdom teeth will be fulfilled. A total of 32 permanent teeth will accompany you until you are as old as Agong.

Maybe you will ask, why do the teeth not grow together and are divided into two stages? This is a clever arrangement of God. When you are very young, the mouth is small and can only hold 20 smaller baby teeth. Wait until you grow taller and taller, and your mouth chamber is getting bigger and bigger, These little baby teeth are not enough. So when you are six years old, the stage of changing teeth begins. But as you will continue to grow up, the second phase of the tooth change will continue until the age of 19, and all 32 permanent teeth will be in place. With so many teeth, and larger in size, it will be a bit crowded in your mouth, and may not be neatly arranged. But no worries, the orthodontist uncle will help you level them, to ensure that the exposed teeth will be all neat and white.

The food we eat is the nutrients for many germs on the teeth. If the teeth or teeth are not cleaned properly, the germs will grow on the teeth and secrete acid that will break the teeth. Now every night you have already developed a good habit of brushing your teeth and flossing. After the permanent teeth grow out, it is more important to keep it that way. Because they are an important tool for enjoying meals and and eating foods in the future, once they are broken, there will be no new teeth to replace. Teeth are important partners in your life, so remember to take care of them and keep them up. Moreover, you need to work hard on drinking milk, because it is rich in Calcium, an important element of teeth and bones that will help you grow more teeth and become taller.

Remember to put the old incisor under the pillow, so that the tooth fairy will come to give you new teeth in the night!

Miss you,

P.S. Grandpa is traveling with grandma in Mainland China and Taiwan now. Therefore, the English version of this letter will be available to you later.