公共英語二級閲讀文章《飼養牡蠣》

對於準備公共英語二級的考生來，儘管公共英語二級難度一般，但是考生如果想要取得比較好的英語成績還是需要認真備考的。下面就為大家送上一篇公共英語二級閲讀文章，歡迎閲讀。

Raising Oysters

In the past oysters were raised in much the same way as dirt farmers raised tomatoes - by transplanting them. First, farmers selected the oyster bed, cleared the bottom of old shells and other debris, then scattered clean shells about. Next, they "planted" fertilized oyster eggs, which within two or three weeks hatched into larvae. The larvae drifted until they attached themselves to the clean shells on the bottom. There they remained and in time grew into baby oysters called seed or spat. The spat grew larger by drawing in seawater from which they derived microscopic particles of food. Before long, farmers gathered the baby oysters, transplanted them in other waters to speed up their growth, then transplanted them once more into another body of water to fatten them up.

Until recently the supply of wild oysters and those crudely farmed were more than enough to satisfy people's needs.

But today the delectable seafood is no longer available in abundance. The problem has become so serious that some oyster beds have vanished entirely.

Fortunately, as far back as the early 1900's marine biologists realized that if new measures were not taken, oysters would become extinct or at best a luxury food. So they set up well-equipped hatcheries and went to work. But they did not have the proper equipment or the skill to handle the eggs. They did not know when, what, and how to feed the larvae. And they knew little about the predators that attack and eat baby oysters by the millions. They failed, but they doggedly kept at it. Finally, in the 1940's a significant breakthrough was made.

The marine biologists discovered that by raising the temperature of the water, they could induce oysters to spawn not only in the summer but also in the fall, winter, and spring. Later they developed a technique for feeding the larvae and rearing them to spat. Going still further, they succeeded in breeding new strains that were resistant to diseases, grew faster and larger, and flourished in water of different salinities and temperatures. In addition, the cultivated oysters tasted better!

飼養牡蠣

過去人們飼養牡蠣的方式很大程度上類似於田地裏的農夫種植蕃茄——通過移植來飼養它們。首先，農夫選好牡蠣苗牀，清除底部的舊殼和其它雜物，然後四處撒播乾淨的殼。接着，他們"栽種"已受精的牡蠣卵。這些卵在 2～3 周內會孵化成幼貝。幼貝一直漂流直到粘在苗牀底部乾淨的殼上為止。它們會呆在那兒並逐漸長成小牡蠣。 我們稱之為種子或貝苗。貝苗吸進海水中的微小生物作為食物從而越長越大。不久之後，農夫將這些小牡蠣收集起來，把它們移種進其他的水域加快其生長，然後再次將它們移種進另外的水域以使其肥壯起來。

直到最近，野生的以及人工飼養的'牡蠣完全能夠滿足人們的需要。

但是今天這種可口的海味已不再大量存在。這個問題已經變得如此嚴重以至於一些牡蠣苗牀已完全消失。

幸運的是，早在20 世紀初期海洋生物學家們就意識到如果不採取新的措施，牡蠣將會滅絕或至少會變為一種奢侈的食品。因此他們建造了裝備良好的孵卵場所並開始工作。但是他們尚沒有適當的裝置或技術來處理牡蠣卵。他們不知道何時、用什麼以及如何餵養幼貝。他們對捕食數百萬幼小牡蠣的動物天敵也所知無幾。他們失敗了，但他們頑強地堅持了下來。終於，在 20 世紀40 年代，一個重要的突破性的進展產生了。

海洋生物學家發現，升高水温能夠誘導牡蠣不僅在夏季也在秋季、冬季和春季裏產卵。後來他們發展了一項技術來餵養幼貝至其長成貝苗。他們進一步成功地培養出了新的品種，可以抵抗疾病、長得更快、更大並且在不同的鹽度和温度的水中都能茁壯生長。此外，這些培殖出的牡蠣口感更佳!

　附：公告英語二級閲讀技巧之以題幹需求、文章大意為目標，速讀全文

這一步驟的有效性，取決於目標是否明確。

一個目標是題幹需求。根據我們從題目中得知的答題目標，在這一步閲讀中要對有關信息進行快速定位，再將相關信息進行整合、辨別、分析、對比，有根有據地排除干擾項，選出正確答案;對與題目無關的信息就可以置之不顧，很快跳躍過去。

第一個步驟許多考生在答題時都是這樣去做的，但同樣的做法，取得的效果卻往往不盡相同，其中當然有各人理解能力的差別，但另外一點原因也不能忽視——這就是對文章大意和主題的把握程度不同。

另一個目標是文章大意。

達成這一目標的方法之一是抓文體要素。考試中，在有限的時間裏，考生必須運用略讀、掃讀、跳讀等技巧，搜尋關鍵詞、主題句，捕捉時空、順序、情節、人物、觀點，並且理清文章脈絡，這樣才能做到快速把握文章大意。不同體裁的文章，文章大意的具體內容也不同。如記敍文多以人物為中心，以時間或空間為線索，按事件的發生、發展、結局展開故事;論述文則包含論點、論據、結論三大要素，通過解釋、舉例來闡述觀點。考生可根據文章的特點，詳讀細節，以動詞、時間、地點、事件、因果等為線索，找出關鍵詞語和主題句。

達成這一目標的方法之二是主題句。抓主題句是快速掌握文章大意的主要方法。多數文段都有主題句，而且主題句一般出現在文章的開頭和結尾。當然也有些文章沒有主題句，需要讀者自己去歸納。因為主題句往往對全文起提示、啟迪、概括、歸納之作用，所以主旨大意題、歸納概括題、中心思想類的題目往往可直接從主題句中找到答案。

比如，請找出下面一段文章的主題句:

The panda is a popular animal. Stories about the panda in the Washington Zoo are always front page news and important features on television newscasts. Stuffed pandas are among the most popular toys for children, and panda postcards are always in demand in zoo gift shops.

不難看出，第一句the panda is a popular animal是主題句，後面的句子都圍繞這個句子展開。