1．In answer to the question of why it happened，I offer the modest proposal that our universe is simply one of those things which happen from time to time.
要回答它为什么出现，我的拙见是，我们的宇宙只是那些不时出现的东西之一。
—Edward P．Tryon
2．Sometimes I think the surest sign that intelligent life exists elsewhere in the universe is that none of it has tried to contact us.
有时我认为外星生物在宇宙存在的最有力的证据就是它从来都没有试图跟我们联系。
—Bill Watterson
Space exploration is of great significance．Through space exploration，we human beings may uncover the unknown resources of the universe．It endows us with knowledge about the origin of life，with which we learn the dangers and make adventures in science and technology．Space exploration also provides a platform for nations to cooperate through participation in joint breakthrough．The space technology plays an indispensable role in our daily life，such as communication and transportation technology．
Astronomy is the oldest science known to man．Thousands of years ago man looked at the stars and wondered about the heavens．But man was limited by the six planets that he could see with his eyes alone．The Greeks studied astronomy over 2，000 years ago．They could see the size，colour，and brightness of a star．They could see its place in the sky．They watched the stars move as the seasons changed．But the Greeks had no tools to help themselves study the heavens．Each new tool added to the field of astronomy helped man reach out into space．Until there were telescopes，man knew a little about the moon．They did not know that the planet called Saturn (土星) had rings around it．Their sight was so limited that they could not see all the planets．In the early 1700s，people thought there were only six planets．Neptune(海王星)，the last of eight planets to be discovered，was not seen until 1846．
Before the spectroscope(分光镜)，man did not know what kind of gases was around the sun or other stars．Without the radiotelescope，we did not know that radio noises came from far in space．Today，astronomy is a growing science．We have learned more in the last fifty years than in the whole history of astronomy．
[探究发现]
1．What could the ancient Greeks see 2，000 years ago when they observed the stars
They could see the size，colour，and brightness of a star．
2．How could we see the gases around the sun
By the spectroscope．1．History is the essence of innumerable biographies．
历史是无数传记的精华。 —Thomas Carlyle
2．History is a philosophy taught by examples．
历史是用事例教育人的哲学。
3．The only thing we learn from history is that we learn nothing from history．
我们从历史中得到的唯一教训就是我们从没在历史中得到任何教训。 —George Bernard Shaw
4．History is the version of past events that people have decided to agree upon．
历史只不过是人们对于过去所发生的事有所认同。
—Napoleon Bonaparte
History is a part of culture，which is the spiritual backbone of a nation.Through learning history，we can appreciate the culture of a country，as well as the history of its development，so that we can understand the nation better.History learning helps us to make correct decisions.By reviewing the history of our nation's development，we are able to avoid some mistakes which we had made in the past and draw lessons from past experience，which is helpful for us to make correct decisions.By learning different ways to solve problems in history，we will be the people with a compressive mind.
The Silk Road is the name of different roads that long ago connected Europe，Africa and Asia．People reached these different places along these roads．Scientists believe people began to travel the Silk Road about 3，000 years ago．By the time the Chinese silk trade became important in the world，the Silk Road covered almost 6，500 kilometres．It spread from Rome to China，which is from the West to the Far East．
Traders travelling along the Silk Road carried silk，of course．They also carried and traded spices(香料)，cloth，valuable stones and gold．
During its busiest period，the Silk Road allowed people from many different cultures and countries to meet each other and mix．The Silk Road allowed the sharing of valuable goods and new ideas．These included people and trading goods from the Mediterranean，Persian，Magyar，Armenian，Bactrian，Indian and Chinese areas．All these peoples travelled the Silk Road，and they shared goods，stories，languages，and cultures．
In modern times，the old Silk Road routes are still used，but now they are crossed by trains instead of camels and horses．There is even a Silk Route Museum in Jiuquan in China．It has over 35，000 objects from all along the Silk Road．In this way，China protects the history of many countries and peoples．
[探究发现]
1．How many kilometres did the Silk Road cover
Almost 6，500 kilometres．
2．What did traders carry along the Silk Road
Silk，spices，cloth，valuable stones and gold．1．The traveller sees what he sees，the tourist sees what he has come to see．
旅行者观称为所看，游览者观称为只看。
—Gilbert K．Chesterton
2．When you travel，remember that a foreign country is not designed to make you comfortable．It is designed to make its own people comfortable．
你在旅行时要记住一点，国外的生活不是为了让你感到舒适。它的设计是为了让其国民感到舒适。 —Clifton Fadiman
When you travel at high speeds，the present means nothing：you live mainly in the future because you spend most of your time looking forward to arriving at some other place．But actual arrival，when it is achieved，is meaningless．You want to move on again．By travelling like this，you suspend all experience；the present ceases to be a reality：you might just as well be dead．The traveller on foot，on the other hand，lives constantly in the present．For him travelling and arriving are one and the same thing：he arrives somewhere with every step he makes．He experiences the present moment with his eyes，his ears and the whole of his body．At the end of his journey he feels a delicious physical weariness．He knows that sound，satisfying sleep will be his：the just reward of all true travellers．
Canada is the second largest country in the world after Russia．It is larger than the USA and reaches nearly a quarter of the way round the earth．The distance from east to west is over 5，500 kilometres and the country covers six of the world's 24 time zones．However，its population，about 37.8 million, is only about one fifth of Russia's．
Nearly 90% of Canadians live within 200 km of the border with the United States，which means that Canada contains vast expanses (宽阔的区域) of wilderness to the north．Canada's native people make up less than two percent of the population．
The weather is different from area to area．In the north，the winters are long and hard，with snow for six months of the year．The temperature can fall to －60℃．The west coast of Canada is the warmest place in winter．The average January temperature is 3℃， and in July it is 18℃．Here it rains a lot every month of the year．Plants grow well all the year round and the parks and gardens are famous for their flowers．
Canada has one third of the world's supply of fresh water．There are five great lakes in the south，and there are many others，especially in the north．Most of the electricity is produced by water．The country has a great deal of coal，oil and natural gas，and these are all exploited(开发) for energy．
[探究发现]
1．Which is the largest country in the world
Russia．
2．Where is the warmest in winter in Canada
The west coast of Canada．1．Books are the legacies that a great talent leaves to mankind．
书籍是伟大的天才留给人类的遗产。 —Edison
2．Culture itself is neither education nor law making；it is an atmosphere and a heritage．
文化本身既不是教育，也不是立法，它是一种氛围，一种遗产。
—H．L．Mencken
3．Book is the precious wealth，a national heritage and history．
书是宝贵财富，是国家的优秀遗产和历史。 —Thoreau
The preservation of our cultural heritage is the necessary task．The culture contains the essence of Chinese people's spirit，which has been tested by time．When people admit our culture，we will be proud of being part of the country，and have the desire to make contributions to society．The loss of cultural heritage will destroy a country，which can be seen in history．
How does a place become a World Heritage Site (世界遗产)？It takes a lot of people to decide．
If a country wants one of its places to be on the World Heritage List，it has to ask UNESCO．But the most important is that the place must be important and special．UNESCO put the Great Wall on the list in 1987，because the Great Wall is a great part of Chinese culture made．When a country asks，it must also make a plan for taking care of the place．
The World Heritage Committee of UNESCO talks about different places and decides whether to put them on the list．The committee meets every June．Many experts help the committee to decide．
After a new place goes on the list，UNESCO gives money to help the country keep it good．If a place is in serious danger，it may be put on the List of World Heritage Sites in Danger．UNESCO will give special care and help to those places．
Countries have to give UNESCO regular reports about places on the list．If UNESCO thinks a country isn't taking good care of a place，the site will be taken off from the list．
[探究发现]
1．When was the Great Wall put on the list of UNESCO
In 1987．
2．What is the reason for some sites taken off from the list
The country is not taking good care of them．
