考研英語作文美文範例指南

考生們在考研英語的複習期間，要找到英語作文的寫作方法，可以參考一些美文範例。小編為大家精心準備了考研英語作文美文參考資料，歡迎大家前來閲讀。

Just how salt became so crucial to our metabolism is a mystery; one appealing theory traces our dependence on it to the chemist ry of the late Cambrian seas. It was there, a half billion years ago, that tiny metazoan organisms first evolved systems for sequestering and circulating fluids. The water of the early oceans might thus have become the chemical prototype

for the fluids of all animal life - the medium in which cellular operations could continue no matter how the external environment changed. This speculation is based on the fact that, even today, the blood serums of radically divergent species are remarkably similar. Lizards, platypuses, sheep, and humans could hardly be more different in anatomy or eating habits, yet the salt content in the fluid surrounding their blood cells is virtually identical. As early marine specics made their way to fresh water and eventually to dry land, sodium remained a key ingredient of their interior, if not their exterior,milieu. The most successful mammalian species would have been those that developed efficient hormonal systems for maintaining the needed sodium concentrations. The human body, for example, uses the hormones renin, angiotensin, and aldosterone to retain or release tissue fluids and blood plasma. The result, under favorable conditions, is a dynamic equilibrium in which neither fluid volume nor sodium concentration fluctuates too dramatically. But if the body is deprived of salt, the effects soon become dangerous, despite compensatory mechanisms.

全文翻譯：鹽與新陳代謝鹽為何成為人類新陳代謝的關鍵是一個謎;一個富有吸引力的理論認為我們對鹽的依 賴可從寒武紀海洋的化學變化中得到線索。五億年前，就是在那裏，微小的後生動物首先 進化成與外隔絕的循環液體系統。因此，早期海洋裏的水可能是所有動物體內液體的化學原型--一個無論外界環境如何改變，其細胞活動仍將繼續的環境。這個設想是建立這一事 實基礎上：即使是在今天，物種迥異的眾多動物血清非常相似。蜥蜴、鴨嘴獸、綿羊和人類，在解剖學和飲食習慣上完全不同，但細胞周圍的液體中的鹽含量卻基本上是相等的。在海洋生物向淡水區域並最終向陸地移動的'過程中，鹽始終是它們生存環境--如果不是外部環 境，其碼也是內部環境中的關鍵成份。 最高級的哺乳類動物為保持所需的鹽濃度而進化出 了高效的內分泌系統。 例如，人體為了保留或釋放組織液體和血漿而使用高血壓蛋白原酶、血管緊張素、醛固酮等激素。這樣在有利的環境下，液體與其中鹽濃度之間形成的動態平衡，兩者均不致出現大起大落。但如果身體裏喪失了的鹽分，儘管有各種的補償機制，後果將馬上極其危險。

To understand the emulsifying process, we must first accept the scientific principle that oil and water do not naturally mix. Quite literally, they find each other's presence repulsive. A good illustration of this aversion is homemade oil and vinegar salad you shake or beat your salad dressing, you do more than disperse the oil throughout the vinegar: you also break down the oil into droplets minute enough to remain temporarily suspended in the vinegar (which from now on we will call water, because that tart condiment is in effect mainly water). The second you stop agitating the dressing, the oil droplets start to combine into units too large to be suspended in the water, and thus slither their way upward, separating from the water in the process. The oil rises to the top and the water sinks because oil has a lower specific density than water. If you want a stable emulsion, you need an emulsifying agent which prevents the oil droplets from combining into larger units. Emulsifying agents occur naturally in many animal substances including egg yolks and milk. An emulsifying agent helps to keep the oil particles from combining in three basic ways. First, the agent coats the oil, serving as a physical barrier between the droplets. Second, it reduces the water's surface tension, which, in turn, reduces the water's ability to repulse oil. Third, the agent gives the surfaces of the oil droplets identical electrical charges; since like charges repel each other the

droplets repel each other.

全文翻譯：油和水為理解乳化過程的發生，我們必須首先認識到這樣一條科學原理：水和油不能自 然混合，它們實實在在互相排斥。 家制的油醋沙拉調料就是一個好例子。 當你攪拌沙拉調 料時，你不僅使油擴散到醋裏，而且使油滴被攪得很小可以懸浮在醋中(自此我們改稱它為 水，因為事實上這種酸性調味品的主要成份就是水)。 一旦你停止了攪動，油滴就會凝聚， 大到再也不能懸浮在水中時，它們就向上滑動出來而與水分離了。 因為油的密度小，所以 油會浮在水上。 如果想得到穩定的乳化，就需要一種乳化劑。 它可以不讓油形成大的油滴。 自然界中，很多動物體中含有乳化劑，如蛋黃和牛奶。乳化劑可以從以下三方面阻止油滴 凝聚。一、 乳化劑包裹住油滴，在油滴間形成一道物質屏障。二、乳化劑降低水的表面 張力，從而降低了水排斥油的能力。 三、 乳化劑使油滴表面帶上了同種電荷，因為同種電 荷互相排斥，油滴之間也相互排斥。

【句型1】+~est+n.+(that)+S+have ever+seen (known/heard/had/read, etc)

most+a.+n.+(that)+S+have ever+seen ( known/heard/had/read, etc)

【例1】Mr. He is the kindest teacher that I have ever had.

【譯文】何老師是我曾經遇到過的最仁慈的教師。

【例2】Helen is the most beautiful girl that I have ever seen.

【譯文】海倫是我所看過最美麗的女孩。

【句型2】Nothing is+~er than to+v.

Nothing is+more+a.+than to+v.

【例句】Nothing is more important than to receive education.

【譯文】沒有比接受教育更重要的事。

【句型3】ot emphasize the importance of ... too much. 再怎麼強調……的重要性也不為過

【例句】We cannot emphasize the importance of protecting our eyes too much.

【譯文】我們再怎麼強調保護眼睛的重要性也不為過。

【句型4】There is no denying that+S+V 不可否認的……

【例句】There is no denying that the qualities of our living have gone from bad to worse.

【譯文】不可否認，我們的生活品質已經每況愈下。

【句型5】It is universally acknowledged that+句子. 全世界都知道……

【例句】It is universally acknowledged that trees are indispensable to us.

【譯文】全世界都知道樹木對我們是不可或缺的。