英语听力材料细菌钟爱你的嘴
彩旗 Did you know that there could be more bacteria living in your mouth than there are people on earth?
你知道吗，寄居于你口中的细菌有可能比全世界的人口数还多?
Bacteria love our mouths becau the livin’ is easy–there’s plenty of food and water, and a fairly constant temperature of 95 degrees. The vast majority of the bacteria don’t cau any problems. Some even do community rvice, cleaning out the food between our teeth without harming the teeth at all!
细菌钟爱我们的嘴是因为口腔中的环境很舒适，不但有充足的食物及水，其温度也稳定在95华氏度。口腔内绝绝大部分的细菌不会产生什么问题。有一部分甚至是有益的，义务清理牙缝中的食物残渣，保护我们的牙齿!
But there is one type of bacteria that wreaks havoc in the mouth by causing cavities. Like most people, the bacterium streptococcus mutans loves to eat sugar. In the process, it conv
erts sugar to an acid that corrodes teeth and caus cavities. Saliva can neutralize some of that acid and prevent it from damaging teeth.
宿的读音
但是有一种细菌会对口腔形成危害，造成蛀牙。细菌中的变形链球菌与很多人一样喜爱吃糖，通过将糖转化为酸，进而腐蚀牙齿，形成蛀洞。唾液能够中和部分酸以防牙齿被损害。
变调夹 But the days, most of us eat so much sugar that our saliva can’t neutralize all the acid that streptococcus mutans produces.
学生餐菜谱 不过现在绝大部分人摄入的糖分过多，以至于唾液无法中和所有的酸，变形链球菌随即而生。
隆昌市 What’s a sugar addict to do?
那么爱吃糖的人该怎么办呢?
If you brush and floss every day, that physically disrupts the colonies of bacteria enough
to keep the populations under control, somewhere between one thousand and one hundred thousand per tooth. The fluoride in toothpaste and tap water hardens tooth enamel, making it more resistant to the acid produced by streptococcus mutans.
如果你每天刷牙并使用牙线清理牙齿，可有效阻断细菌繁殖，将每颗牙的细菌数控制在一千至十万。牙膏中的氟化物及自来水也能够坚固牙釉质，使牙齿更好的抵御变形链球菌所产生的酸。
描写心情的好句 Fluoride also helps saliva repair parts of the tooth that have already been damaged by the acid. And, last but not least, it helps not to feed the critters too much of their favorite food： sugar!化学英语单词
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