Eg： Scientists are in search of a cure for the disease. 科学家正在想治疗这种疾病的方法。
3.to …degree 达到…程度
to some degree 达到一定的程度
to what degree 达到什么程度
to a high/low degree 达到很高/低的程度
to such an degree 达到如此…的程度
to a certain degree 达到一定的程度
E.g. He is vain to a high degree. 他非常爱虚荣。
4.to some extent 在某种程度上
E.g.： To some extent you are correct . 从某种程度上说你是正确的。
I agree with you to a certain extent. 我在一定程度上同意你的意见。
5.prevent … from 防止，阻止
E.g.： Put on more clothes to prevent yourself from getting a cold. 多穿点衣服，以免感冒。
6.in turn 1.依次，轮流；2.反过来
by turns 轮流，交替
1）please speak in turn. 请依次发言。
2）Theory is based on practice and in turn serves practice. 理论以实践为基础，反过来又为实践服务。
3）The couple wash dishes by turns. 夫妻俩轮流洗碗
7.result in = bring about 导致，产生
E.g.： Our efforts resulted in success. 我们的努力终于导致了成功
→result from 因为…。发生，产生
E.g.： His injury resulted from a fall. 他因摔倒而受伤。
Ⅱ.Text B
Life on the Tundra
冻土带上的生活情景
Tundra is the name given to the low， marshy plains of Europe， Siberia， and North America that border on the Arctic Ocean.
译：欧洲、西伯利亚和北美洲接近北冰洋的低洼沼泽平原称为冻土带。
1.border on 与…相邻
In Alaska， the vast， cold region known as the “Northern Slope” is part of the tundra. Nature sets harsh terms for survival in this land. Only those plants and animals that are adapted to the hostile environment can survive in it.
2.be know as
terms 条件（如果去掉s则没有条件的意思，表示“学期；术语”）
3.adapt to 适应…
译：美国阿拉斯加州，那块广阔寒冷通称为“北边坡地”的地区就是冻土带的一部分。大自然为这片土地设置的生存条件十分恶劣。只有那些能适应在逆境中生存的植物和动物才能在这种环境中生存下来。
Long periods of darkness and bitter cold are the major threats to life on the tundra. At the Arctic Circle， the sun cannot be seen above the horizon in December. North of the Circle， the darkness lasts even longer. Over the northern reaches of the tundra， no sunlight can be seen at all for several months of the year.
bitter 在这里表示“刺骨的”
4.over ： beyond在…以外
5.no … at all： not … at all 一点也不，根本不
eg. You don't look old at all. 你看起来一点也不老。
译：长期的黑暗和刺骨的严寒是在冻土带上生活的两大最主要的威胁。北极圈在12月份，地平线上是看不到太阳的。从北极圈往北黑暗的时间通常会持续得更长些。在冻土带北部边缘以外的地方，一年中有好几个月根本见不到阳光。
The darkness is balanced， to some degree， by continuous daylight during the summer months.
译：持续的黑暗，从某种意义上来说，同夏季几个月连续不断的白昼达到了平衡。
6.Balance n. 平衡
v. 使…平衡，使…均衡
But even in the warmest month， the temperature only averages about 50 degree F （10 degrees C）。
F（fahrenheit） C（centigrade）
Boiling point 212° 100°
Freezing point 32° 0°
Absolute-zero -459.67° -273.15°
换算公式：
摄氏度数＝（华氏度度数－32）×5/9
华氏度数＝摄氏度度数×9/5 ＋32
译：但即使是在最暖和的月份里，平均温度刚刚能达到华氏50度（10摄氏度）。
During the dark winter months the average temperature falls to -16 degrees F （ -27 degrees C）， and sometimes to -40 degrees （C and F） and below.
译：在冬季那几个黑暗的月份里，平均气温降到华氏负16度，有时达零下40度甚至更低。
Because of the intense cold， the subsoil of the tundra remains permanently frozen to a great depth. During the brief summer， a few feet （about a meter） of soil thaw at the surface. It is this thin layer of active soil that supports all living things on the tundra.
译：由于酷寒，冻土带的下层土都冻得很深。在短暂的夏季仅三英尺的表层土壤能解冻。正是这被太阳晒暖的苏醒过来的薄薄的一层土壤养活着冻土带上的一切生物。
For nine months of the year， the tundra is a dark， seemingly lifeless wild land. Then in June， as if by magic， a never-setting summer sun gives birth to hundreds of species of arctic plants to cover the ground.
7.give birth to （prep.） 产生…，生产出…
译：每年长达9个月，冻土带都是一块看上去毫无生机的荒凉的土地。然后到6月份，好像是施了魔法一样，一轮永不落的夏天的太阳生出了数百种北极的植物覆盖着大地。
A plant that grows more than three feet （about a meter） is unusual on the tundra. There are no tall trees. The frozen subsoil prevents roots from growing deep enough to support them. By the end of August the breath of winter returns， and by mid-September the tundra is white again.
译：一种植物若能长得超过了三英尺，这在冻土带上就是很不平常的了。冻土带上根本就不会有高大的树木。深层的永冻土使植物的根不能深深地扎下去来支撑高大的树木。到8月底，冬天的气息又返回来了， 9月中旬这冻土带又是冬天了。
The animal life on the tundra is unusually rich for an environment that seems so harsh. Herds of arctic deer move from place to place in search of food. Bands of wolves follow them and hunt for the weak or sick ones.
rich adj.富的， 有钱的， 富有的， 富饶的， 肥沃的， 充足的， 丰富的
表示数量的词：
herds of deer 一群群的鹿
bands of wolves 一群群的狼
a group/crowd of people 一群人
a herd of cattle 一群牛
a flock of birds 一群鸟
a nest of ants 一群蚂蚁
译：在这种非常恶劣的环境中，冻土带上动物的生活却非常充实。一群一群的北极鹿到处迁徙以便寻找食物。一帮一帮的北极狼跟踪着北极鹿群以便猎吃鹿群中的老弱病残者。
Few birds actually live on the tundra. However， a variety of birds migrate to nest and feed during the summer. The wet， marshy land produces a large number of insects that provide food for the smaller birds that， in turn， provide food for the arctic fox and the wolf.
8.a variety of ： various of ： 多种多样的
译：实际上几乎没有鸟类生活在冻土带上。但是各种各样的候鸟到了夏季会到这里来筑巢繁衍生息。这湿润的沼泽地能生出大量的昆虫，这就给小鸟提供了食物。接下来这些小鸟又充作了北极狐和北极狼的食物。
The balance of nature is so delicate on the tundra that even minor disturbances may produce major changes in the environment.
译：自然界的平衡在冻土带上是非常灵敏的，只要稍微有一点破坏平衡的现象出现就可能产生环境上的一些重大变化。
Any increase or decrease in the population of one species may affect all other species on the tundra. For example， if the number of wolves and foxes decrease， the food chain is upset.
译译：任何一个物种在数量上的增加或减少都会影响到冻土带上所有的其它物种。例如，如果北极狼和北极狐的数量减少，那食物链就会遭到破坏，就会脱节。
Without wolves， the number of grazing animals - like the deer - would increase. This increase would result in a food shortage， which would cause death to many smaller animals. A decrease in the number of these smaller animals would in turn decrease the food supply for the arctic fox and the wolf. In this way， the entire food chain might be affected by a change in the number of a single species.
译：倘若没有了北极狼，那些食草兽——像驯鹿之类——就会增加，这一增加就会导致食物短缺，很多小动物就会死亡。倘若这些小动物数量减少了，接下来就会减少了供应给北极狐和北极狼的食物。这样下来，由于某一物种的数量的改变，就有可能影响到整个食物链的脱节。
Until recently， the changing seasons on the tundra were seen only by a few Eskimo hunters and explorers. What would draw men and women to live in such a hostile land？ The answer is oil.
译：不久前，只有极少数的爱斯基摩的猎手和探险家才能深究到冻土带上的寒来暑往，冬去春来。那么，是什么东西把男男女女都吸引到这块环境十分恶劣的土地上来的呢？答案就是：石油。
9.draw （v.）： attract 吸引
In 1968， oil was discovered beneath the frozen soil on Alaska's Northern Slope. Now an 800-mile （about 1300 kilometers） pipeline has been built from Prudhoe Bay on the Arctic Ocean to Valdes， a port on the south coast of Alaska.
译：1968年在阿拉斯加北边坡地的冻土下面发现了石油。现在已经把一条800英里长的输油管从北冰洋上的普拉德霍湾架设到了阿拉斯加南岸的港口城市瓦尔迪兹。
The pipeline carries the oil from the Northern Slope， across the tundra， to the port. From there， it is shipped to the rest of the United States.
译：这条输油管把石油从北部坡地，越过冻土带，输送到瓦尔迪兹港口，又从那里把石油装船运送到美国其它地方。
10.ship （v.） 运送，输送
Thousands of men and women were needed to build and maintain the pipeline. For the first time， large numbers of people were brought into contact with the tundra.
译：为了修建和维护这条输油管，成千上万的男女需要参与工作。这是破天荒第一次，把一大批又一大批的人送到这里来与冻土带打交道。
Their presence and the presence of the pipeline they built represented a major change in the environment. How will the life cycles of the tundra be affected？
译：这些人的到来以及他们所修建的输油管的出现标志着冻土带的环境的重大改变。那么，冻土带的生活周期会受到什么影响呢？
The survival of the United States depends on the ability to find new sources of energy. Oil from beneath the tundra is very important to the nations' development. But the survival of the tundra depends on how carefully people maintain the delicate balance of nature in this environment.
译：美国能否继续生存下去，依赖于是否有能力找到新的能源。来自冻土带下面的石油对美国的发展至关重要。但是，这块冻土带上的一切是否能继续维持下去，依赖于人们是否能细心地维护这种环境下大自然里各个物种之间的平衡。
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