新编英语教程第二册Unit07

Unit 7

DIALOGUE I

The Western Frontier in the United States

A: Hank, I've heard about the westward 1 movement of population in the United States in the nineteenth century. I'm very interested in that part of your history. Could you tell me more about the American western frontier.
B: Yes, of course. The life of the frontiersmen in the West has always been an attraction to us American people, especially to American boys. I used to be enthralled 2 by what my grandmother told me about her grandfather. He was a pioneer going west in the early days.
A: Really? Her accounts must be authentic 3. What did she tell you?
B: In the early 1870s my great-great-grandfather came to the "new continent" as an immigrant from Ireland. For some time he was quite unhappy about his life as a craftsman 4. Then he heard that gold had been found in the West. Like many other Easterners then, he felt an urge to go west and seek his fortune. So he took the wagon 5 trek 6 across the plains and deserts.
A: The wagon what?
B: Oh, the wagon trek. T-R-E-K. It means a long, hard journey by wagon. In those days the only means of transportation for the frontiersmen was the covered wagon. And there were only very rough paths. The journey was not only long but risky 7, too.
A: Did he travel to a village or a town, or the outskirts 8 of a city?
B: Oh, no, the frontier had none of those. It was a place where people had just settled down, and beyond the settlement it was just wild, uncultivated land except for the Indian people who had lived there in their communities for thousands of years. So life there was crude and rough.
A: They must have had a hard time getting adjusted to the new environment. What kind of houses did they live in?
B: If they happened to be near a forest, they built log cabins. What my great-great-grandfather had was a log cabin with no door, no window, and no chimney.
A: Without a door or window? How did they get into the cabin?
B: There was a hole in the wall. They had to crawl in and out of the cabin through the hole. Every night they stuffed the hole with a large rock to keep out wild animals. You see, it was the wild west then.
A: What a dreadful life! What made the frontiersmen so strong-willed as to endure all these hardships?
B: Most of them had been oppressed in one way or another. They had been attracted by the wide stretches of land that they could get, and there were the gold mines, and they prayed for a lucky strike.
A: In such a wild place, what did they eat?
B: They ate whatever was available, mostly wild deer and elk 9, and bison in the early days. Then there was all the land for them to cultivate.
A: Those people were really fearless and self-reliant. What an incredible pioneering spirit they had!
B: That's perhaps one reason why we Americans still look back to the pioneers with respect and admiration 10.

DIALOGUE II

Dialogue:

Two men are chatting in their office, just before they leave for their holidays.
A: You must be excited at the prospect 11 of starting your holiday next week.
B: Yes, I am. I've been looking forward to it for ages. It seems such a long time since I had a holiday.
A: What about your wife?
B: Oh, she's desperate to get away too. She's anxious to see her parents again.
A: Oh, you'll be staying with the in-laws then?
B: Yes, for most of the time, but the kids are really keen on the idea of spending a few days camping.
A: It'd be nice to go camping. I must say I'm looking forward to this break too.
B: You haven't decided 12 where you are going then?
A: No, not exactly. I'd love to go abroad, but I can't afford it at the moment. I may borrow my brother's bike and go on a cycling tour of the Lake District. Two weeks isn't really long enough though, to do justice to the Lakes.
B: Wouldn't it be lovely to have a really long holiday; say, a couple of months?
A: Yes, marvelous! I'd give anything for a long, relaxing holiday!
B: Still, 2 weeks isn't bad. We should count ourselves lucky. Let's just enjoy it.

READING I

Intelligence in Animals

Before considering this question it is interesting to review briefly 13 the evolution of the mind as an instrument. The commonest way that has been used to find out the relative intellectual levels of creatures at different stages of evolutionary 14 complexity 15 has been to study the way they behave when set different kinds of puzzles. For example, an ant possesses a complex routine of behaviour, but can it think? The answer is that if an ant is forced to go through a maze 16 of passages, many of which are dead ends, on its way to its nest, it starts by making a lot of mistakes and taking a great many wrong turnings. In the end, however, after it has had to worry its way through often enough, it does learn to get to its nest without going into any of the blind alleys 17. As one moves up the evolutionary scale the test of brain-power exemplified by solving the problem of getting through a maze becomes too simple. Among mammals, for example, the maze is an inadequate 18 test. The learning problem does not tax enough attributes of the mind. In this sort of learning, as a matter of fact, rats can beat university undergraduates and have, in fact, repeatedly done so.
The next, more subtle test of mental ability is to see at what level an animal can think about something when it is not there. The usual test is to train the animal to go through one of several doors when a light is turned on at that particular door. When the preliminary lesson has been learnt-that is, that food can be obtained by going through the door with the light-the more subtle trial is imposed. The light is shone as before at one or other of the different doors and is then extinguished. After an interval 19 the animal is released. When posed with this test rats and dogs can remember which was the lighted door only if they are allowed to keep their heads steadily 20 pointing at where the light was. On the other hand, a raccoon, possessing a more highly evolved brain, can pace up and down until it is released and then go straight to the correct door. But it can only remember for about twenty-five seconds which is the right door for any particular test.
Monkeys and chimpanzees, although they are weaker and less fierce than many other animals, possess brains which are as far along the evolutionary road as any creature other than man. Birds can perform marvels 21 of aerobatics, they can catch insects on the wing with unparalleled skill, they can navigate 22 in a remarkable 23 manner half round the world and back -- but they cannot think and reason. In technical terms it can be said that they are lacking in insight. The abilities which they do possess are built-in instincts derived 24 from their genetic 25 inheritance. Monkeys, on the other hand, can reason. They can easily remember a lighted door indicating the presence of food. They can remember what kind of food they are looking for. A monkey set the problem of reaching a banana, say, hung high up in its cage can work out a system for getting it even if it involves piling up boxes to stand on and then knocking down the banana with a stick. A charming story is told about the psychologist Wolfgang Kohler, who had provided various boxes and other gear by which he proposed to test a chimpanzee's ability to think out a method of reaching a fruit hung nine feet in the air. The animal looked about it and sized up the problem. Then it took Kohler by the hand, led him to a position immediately under the banana, jumped up on to his shoulder and reached it down from there.
But evolution, although it has brought monkeys to a remarkable degree of cleverness, has stopped short at a crucial ability, the possession of which places man at a clearly superior level. Their minds cannot cope with abstract ideas. For example, an ape can be taught to fill a can with water from a barrel and take the can of water to extinguish a fire so that it can reach into a box and get food. But if the whole set-up is arranged on a raft the animal will continue to draw its water only from the barrel. It cannot grasp that any water, taken more conveniently, say, from the pond on which the raft is floating, will put out the fire just as well. The abstract idea that water quenches 26 fire is beyond it.

READING II

How Animals Keep Warm

Man, from the moment he appeared on earth, has had to use all his powers of thinking and reasoning to combat his enemies. In northern regions, or at great altitudes, cold can be severe and is an enemy indeed.
Man has invented ways to keep warm, but how do animals defend themselves? They cannot reason in the sense that man can, but nature has taken care of the animal kingdom by providing animals with special instincts. One of these instincts is known as hibernation 27.
"Sleeping like a dormouse" is not only a common saying but is a reality. When winter comes, the dormouse and other hibernating 28 animals have reached a well-nourished state. They eat very well in warmer days, laying down fat in the tissues of their bodies and during hibernation this keeps them alive. Safe in their nests, or burrows 30, they sleep soundly until the warmth of spring arrives.
Bats, porcupines 31, tortoises, lizards 32, snakes, frogs, even insects like butterflies, hibernate 33 more or less completely. Some, like the squirrels, sleep during the coldest weather but are roused by a warm spell. During hibernation, the temperature of an animal's body falls to 40°F (4.4° Celsius), or even as low as 20°F ( - 6.6° Celsius). Breathing and heart-beat almost cease.
Another instinctive 34 method of avoiding intense cold is to escape by means of migration 35. Wild swans, storks 36, seagulls, swallows and cuckoos are a few of the very many kinds of birds which fly thousands of miles, twice a year, to avoid cold. Many animals, especially those of the Arctic regions, have summer and winter quarters. The caribou 37 and the Arctic deer of North America, as well as the reindeer 38 of Europe, move southward towards the forests when winter approaches. They return to the northern tundra 39 when the warmth of spring begins to be sensed.
There are animals which do not attempt to leave at the first sign of winter cold. Their instinctive means of defence is to dig out a deep burrow 29, made soft and warm by padding out with straw, leaves, moss 40 and fur. In it they have a "larder 41" containing food which they hope will last the winter through. Animals which fall into this class include those of the Alpine 42 regions: the Arctic fox, the rabbit and the ermine, and the little field-mice.
In the most northern and icy regions of the earth, the Polar bear passes the winter in a deep cavity which is covered over with snow and ice. He, too, lays in a good stock of food, and eats as much as he can before sleeping.