你对牙齿了解多少

Everybody hasteeth. We all know that teeth help us eat. But is that all about teeth? How much do you know about teeth?

每个人都有牙齿。我们都知道牙齿帮助我们吃东西。但是，这就是牙齿的全部吗？你对牙齿又了解多少呢？

1. Why do you need to brush your teeth every day? Why is there tooth decay?

为什么需要每天刷牙？为什么会有蛀牙？

It is veryimportantto brush your teeth every day,otherwisesuchcavitieswill grow on your teeth. Cavities areholesthat grow in your teeth. If you do not brush your teeth often, there will be some smallfood residuesleft in thegapsbetween the teeth after these residues as food, and they willincrease. Bacteria will produce something called “acid”, which cancorrode , the foodremainingon the teeth will help the bacteria to growcontinuously, the hard teeth will be corrodedlittle by little,and the teeth willformsmall holes, which are cavities. A tooth with a hole is a tooth decay.

每天刷牙是非常重要的，否则牙齿上就会长出这样的龋洞。龋洞，就是牙齿里长出来的洞。如果经常不刷牙，吃东西以后，会有一些细小的食物残渣留在牙齿缝里。细菌拿这些残渣当食物，就会繁殖得越来越多了。细菌会制造一种叫“酸”的东西，它能腐蚀坚硬的东西。所以残留在牙齿上的食物就会帮助细菌不断生长，坚硬的牙齿就会一点一点地被腐蚀，牙齿就会形成一个一个小洞洞，这就是龋洞。有了洞洞的牙齿，就是蛀牙。

2. How do teeth work?

牙齿怎么工作？

There are differenttypesof teeth in our mouth. The front teeth are called front teeth, and the teeth next to the front teeth are pointed, calledfangs. Look at the teeth at the aremolars. Put the food in the mouth, the front teeth like achiselwill cut off the food; thesharpteeth like anawlwill helptearthe foodapart; the molars like astone mortarwillgrindthe food so that when the food enters thestomach, we can get itnutrition.

我们嘴巴里有各种不同类型的牙齿，最前面的牙齿叫作门牙，门牙旁边的牙齿是尖的，叫作尖牙。看看那些位置靠后的牙齿，它们是磨牙。把食物放进嘴里，像凿子一样的门牙会把食物切断；像锥子一样的尖牙会帮忙撕开食物；像石臼一样的磨牙会把食物磨碎，这样食物进入肚子后，我们就可以得到营养。

3. How many teeth do we have?

我们有几颗牙齿？

Wegenerallystart to growdeciduous teethfrom 6 months old, and we have 20 deciduous teeth when we grow to about 2 and a half years old. At the age of six or seven, they will fall one by one, and newpermanent teethwill have 28-32 permanent teeth. Everyone has only one chance to change permanent teeth.

我们一般从6 个月开始长乳牙，长到2 岁半左右共有20 颗乳牙。在六七岁时乳牙会一颗一颗掉落，再长出新的恒牙。成年人有28 ～32 颗恒牙。每个人都只有一次换恒牙的机会。

4. How to protect teeth?

怎么保护牙齿？

Brush your teeth! Toremovethe food residue left between the teeth, you need to brush your teeth. Also, don’t eat too many this way, we will havehealthyteeth!

刷牙！要把留在牙缝里的食物残渣清除干净，就需要刷牙。另外，不要吃太多的甜食。这样，我们就会有健康的牙齿啦！

Notes:

teethn.（tooth 的复数）牙齿

tooth decay蛀牙

importantadj.重要的

otherwiseadv.除非

cavityn.龋洞

holen.洞；空腔

food residue 食物残渣

gapn.缝隙

bacterian.细菌

increasev.增长；增加

acidn.酸

corrodev.侵蚀

hardadj.硬的

remainv.保留

continuouslyadv.不断地

little by little 一点一点地

formv.形成

typen.类型

fangn.尖牙

molarn.磨牙

chiseln.凿子

sharpadj.锋利的

awln.锥子

tear … apart把……撕开

stone mortar 石臼

grindv.磨

stomachn.胃；肚子

nutritionn.营养

generallyadv.一般地

deciduous teeth 乳牙

permanent teeth 恒牙

adultn.成年人

protectv.保护

removev.移动

in this way 这样

文章来源：《腐蚀科学与防护技术》 网址: http://www.fskxyfhjszz.cn/qikandaodu/2021/0606/801.html