In the oysters2 were raised in much the same way as dirt farmers raised tomatoes- by transplanting them. First, farmers selected the oyster1 bed, cleared the bottom of old shells and other debris3, then scattered4 clean shells about. Next, they ”planted” fertilized5 oyster eggs, which within two or three weeks hatched into larvae6. 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 spat7. The spat grew larger by drawing in seawater from which they derived8 microscopic9 particles of food. Before long, farmers gathered the baby oysters, transplanted them once more into another body of water to fatten10 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 delectable11 seafood12 is no longer available in abundance. The problem has become so serious that some oyster beds have vanished entirely13.
Fortunately, as far back as the early 1900’s marine14 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 predators15 that attack and eat baby oysters by the millions. They failed, but they doggedly16 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 spawn17 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 resistant18 to diseases, grew faster and larger, and flourished in water of different salinities and temperatures. In addition, the cultivated oysters tasted better!
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收听单词发音
1
oyster
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n.牡蛎;沉默寡言的人 |
参考例句: |
- I enjoy eating oyster; it's really delicious.我喜欢吃牡蛎,它味道真美。
- I find I fairly like eating when he finally persuades me to taste the oyster.当他最后说服我尝尝牡蛎时,我发现我相当喜欢吃。
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2
oysters
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牡蛎( oyster的名词复数 ) |
参考例句: |
- We don't have oysters tonight, but the crayfish are very good. 我们今晚没有牡蛎供应。但小龙虾是非常好。
- She carried a piping hot grill of oysters and bacon. 她端出一盘滚烫的烤牡蛎和咸肉。
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3
debris
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n.瓦砾堆,废墟,碎片 |
参考例句: |
- After the bombing there was a lot of debris everywhere.轰炸之后到处瓦砾成堆。
- Bacteria sticks to food debris in the teeth,causing decay.细菌附着在牙缝中的食物残渣上,导致蛀牙。
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4
scattered
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adj.分散的,稀疏的;散步的;疏疏落落的 |
参考例句: |
- Gathering up his scattered papers,he pushed them into his case.他把散乱的文件收拾起来,塞进文件夹里。
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5
Fertilized
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v.施肥( fertilize的过去式和过去分词 ) |
参考例句: |
- The study of psychology has recently been widely cross-fertilized by new discoveries in genetics. 心理学研究最近从遗传学的新发现中受益匪浅。
- Flowers are often fertilized by bees as they gather nectar. 花常在蜜蜂采蜜时受粉。
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6
larvae
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n.幼虫 |
参考例句: |
- Larvae are parasitic on sheep.幼虫寄生在绵羊的身上。
- The larvae prey upon small aphids.这种幼虫以小蚜虫为食。
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7
spat
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n.口角,掌击;v.发出呼噜呼噜声 |
参考例句: |
- Her parents always have spats.她的父母经常有些小的口角。
- There is only a spat between the brother and sister.那只是兄妹间的小吵小闹。
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8
derived
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vi.起源;由来;衍生;导出v.得到( derive的过去式和过去分词 );(从…中)得到获得;源于;(从…中)提取 |
参考例句: |
- Many English words are derived from Latin and Greek. 英语很多词源出于拉丁文和希腊文。 来自《简明英汉词典》
- He derived his enthusiasm for literature from his father. 他对文学的爱好是受他父亲的影响。 来自《简明英汉词典》
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9
microscopic
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adj.微小的,细微的,极小的,显微的 |
参考例句: |
- It's impossible to read his microscopic handwriting.不可能看清他那极小的书写字迹。
- A plant's lungs are the microscopic pores in its leaves.植物的肺就是其叶片上微细的气孔。
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10
fatten
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v.使肥,变肥 |
参考例句: |
- The new feed can fatten the chicken up quickly enough for market.新饲料能使鸡长得更快,以适应市场需求。
- We keep animals in pens to fatten them.我们把动物关在围栏里把它们养肥。
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11
delectable
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adj.使人愉快的;美味的 |
参考例句: |
- What delectable food you cook!你做的食品真好吃!
- But today the delectable seafood is no longer available in abundance.但是今天这种可口的海味已不再大量存在。
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12
seafood
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n.海产食品,海味,海鲜 |
参考例句: |
- There's an excellent seafood restaurant near here.离这儿不远有家非常不错的海鲜馆。
- Shrimps are a popular type of seafood.小虾是比较普遍的一种海味。
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13
entirely
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ad.全部地,完整地;完全地,彻底地 |
参考例句: |
- The fire was entirely caused by their neglect of duty. 那场火灾完全是由于他们失职而引起的。
- His life was entirely given up to the educational work. 他的一生统统献给了教育工作。
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14
marine
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adj.海的;海生的;航海的;海事的;n.水兵 |
参考例句: |
- Marine creatures are those which live in the sea. 海洋生物是生存在海里的生物。
- When the war broke out,he volunteered for the Marine Corps.战争爆发时,他自愿参加了海军陆战队。
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15
predators
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n.食肉动物( predator的名词复数 );奴役他人者(尤指在财务或性关系方面) |
参考例句: |
- birds and their earthbound predators 鸟和地面上捕食它们的动物
- The eyes of predators are highly sensitive to the slightest movement. 捕食性动物的眼睛能感觉到最细小的动静。 来自《简明英汉词典》
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16
doggedly
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adv.顽强地,固执地 |
参考例句: |
- He was still doggedly pursuing his studies.他仍然顽强地进行着自己的研究。
- He trudged doggedly on until he reached the flat.他顽强地、步履艰难地走着,一直走回了公寓。
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17
spawn
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n.卵,产物,后代,结果;vt.产卵,种菌丝于,产生,造成;vi.产卵,大量生产 |
参考例句: |
- The fish were madly pushing their way upstream to spawn.鱼群为产卵而疯狂地向上游挤进。
- These fish will lay spawn in about one month from now.这些鱼大约一个月内会产卵。
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18
resistant
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adj.(to)抵抗的,有抵抗力的 |
参考例句: |
- Many pests are resistant to the insecticide.许多害虫对这种杀虫剂有抵抗力。
- They imposed their government by force on the resistant population.他们以武力把自己的统治强加在持反抗态度的人民头上。
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