英語作文的優美文摘
想要提高英語作文的水平就是要多多積累英語文章哦，小編今天給大家整理了英語的文摘，只要我們認真的學習這樣纔可以快速的提高成績，所以同學們快點學習起來吧，有需要的可以收藏起來哦
細菌鍾愛你的嘴
Bacteria Loves Your Mouth
細菌鍾愛你的嘴
Did you know that there could be more bacteria living in your mouth than there are people on earth?
你知道嗎，寄居於你口中的細菌有可能比全世界的人口數還多?
Bacteria love our mouths because the livin’ is easy–there’s plenty of food and water, and a fairly constant temperature of 95 degrees. The vast majority of these bacteria don’t cause any problems. Some even do community service, cleaning out the food between our teeth without harming the teeth at all!
細菌鍾愛我們的嘴是因爲口腔中的環境很舒適，不僅有充足的食物及水，其溫度也穩定在95華氏度。口腔內絕大多數的細菌不會產生什麼問題。有一部分甚至是有益的，義務清理牙縫中的食物殘渣，保護我們的牙齒!
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 converts sugar to an acid that corrodes teeth and causes cavities. Saliva can neutralize some of that acid and prevent it from damaging teeth.
但是有一種細菌會對口腔形成危害，造成蛀牙。細菌中的變形鏈球菌與許多人一樣喜愛吃糖，通過將糖轉化爲酸，進而腐蝕牙齒，形成蛀洞。唾液能夠中和部分酸以防牙齒被損害。
But these days, most of us eat so much sugar that our saliva can’t neutralize all the acid that streptococcus mutans produces.
然而現在大部分人攝入的糖分過多，以至於唾液無法中和所有的酸，變形鏈球菌隨即而生。
What’s a sugar addict to do?
那麼愛吃糖的人該怎麼辦呢
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.
如果你每天刷牙並使用牙線清理牙齒，可有效阻斷細菌繁殖，將每顆牙的細菌數控制在一千至十萬。牙膏中的氟化物及自來水也能夠堅固牙釉質，使牙齒更好的抵禦變形鏈球菌所產生的酸。
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!
氟化物還能夠幫助唾液修復被酸損害的部分牙齒。最重要的一點就是不要給細菌它們的最愛——糖。
石英計時
Keeping Time With Quartz
石英計時
Most people know that wrist watches commonly contain quartz. In fact, if you wear a watch, chances are it’s a quartz watch, since most watches is made today use quartz. But, you may not know what quartz has to do with keeping time.
大多數人都知道通常腕錶內含有石英。事實上，只要你帶表，那基本上都是石英錶，因爲當今通用的多數表都由石英制造。但是，你可能不知道石英與計時之間有何關聯。
Quartz is a mineral, otherwise known as silicon dioxide, which is common in the earth’s crust, and the main ingredient of sand. This mineral is popular with watch manufacturers because it vibrates quickly when electrically stimulated, and loses little energy when vibrating.
石英是一種礦物質，也就是二氧化硅，通常存在於地殼中，同時也是沙子的主要成分。石英常被用於製作鐘錶是因爲這種礦物質在受到電刺激後會快速擺動，而擺動過程中的能量損耗很小。
The steady vibrations are what allow a watch to keep time. The quartz used in watches is actually synthetic, because it vibrates more steadily than natural quartz.
這種平穩的擺動就是手錶計時的奧妙所在。手錶所用的石英實際上是合成的，合成石英比自然石英擺動得更爲穩定。
Here’s how a quartz watch works. A small, paper-thin piece of synthetic quartz acts as the watch’s oscillator. Think of the oscillator like the pendulum in a grandfather clock, that by its continuous motion tells the watch how much time has passed. The oscillator is a sort of counter which ticks off the seconds, minutes and hours, and the watch displays the time counted.
現在讓我們來探尋石英手錶的工作原理。微小如紙薄的合成石英相當於手錶的振盪器。這種振盪器如同座鐘的鐘擺，通過它不間斷的擺動反饋到手錶來提示時間。振盪器是一種標記秒、分及小時的計算器，而手錶則顯示出所記時間。
When the quartz oscillator receives an electrical charge from a battery or some other power source, it vibrates at over 32,000 times per second. As it vibrates, an integrated circuit in the watch programmed to know the oscillator’s frequency regulates the vibrations so that a certain number of them equals one second.
當石英振盪器接收到來自電池或其他電源的電荷時，它將以超過32,000次/秒的頻率擺動。擺動過程中，通過編程手錶中的集成電路來測定振動器的頻率，進而調整擺動，以達到固定擺動次數爲一秒。
If the watch has a minute and second hand, the regulated electrical pulses are changed into mechanical pulses that move gears and set the watch hands in motion. If the watch is digital, the quartz’s electrical impulses add up to minutes, hours, and days.
如果手錶有分針和時針，設置好的電脈衝可轉換成機械脈衝，推動齒輪轉動進而帶動指針運動。若是電子手錶，石英的電脈衝可累計成分鐘、小時及天數。
