What do the five Olympic signs on the flag represent?     1     is widely believed that the five-riing Olympic symbol was created by Frenchman Pierre De Coubertin in 1913. As the founder of the modern Olympic Games, he wanted     2    (celebrate) the 20the anniversary(周年纪念) of the Games and chose a design of five rings,     3     represented the five continents(洲) taking part in the Games. The rings     4    (become) the official Olympic symbol at the 1920 Games in Belgium.

Pierre de Coubertin thought that the five interlocking rings meant the five continents     5    (compete) in the Games and the meeting of their athletes at the Olympic games.     6    (actual) every part of the modern Olympic symbol and flag shows the main purpose of the Games in a particular way. The Olympic flag, with its familiar rings, is used as     7     international symbol of peace, unity and     8    (agree). The white background of the flag stands     9     peace and truth.

At the end of each Olympic Games, the mayor(市长) of the hosting city passes the Olympic fag to the mayor of the city where the next Olympics     10    (hold) for years later. The flag remains there until the next Olympics.

As is     1     (know) to all, the Olympic Games are the most important events in the world. They were first held in ancient Greece     2     776 BC. And the events were named after the city Olympia. Slaves and women could not be allowed to take part in the ancient Olympics, and the     3     (athlete) were all from the same country.

In 1896,     4     first modern Olympics opened in Athens, the capital city of Greece. From then on, the Olympic Games     5     (take) place every four years. Athletes from the whole world can take part in the     6     (importance) events, whether they are men or women. The five rings on the Olympic Flag stand     7     five continents and the union of the whole world.

China didn't become a member of the modern Olympics until the 1950s. And in 1984, Xu Haifeng became the first Chinese that won an Olympic gold medal in shooting. With the     8     (develop) of China, Beijing finally succeeded in     9     (hold) the 2008 Olympics, during which the five Fuwa mascots     10     (deep) impressed the whole world.

Clowns (小丑)are almost everywhere in popular culture. But what they represent     1    (change) a lot over the past 400 years.

Clowns began appearing in     2     form we recognize today in European theaters in the 17th century. With brightly colored clothes, big red noses and colorful faces, clowns tried every means to act foolish or play tricks     3     (make) the audience laugh.

Clowns became popular in the US in the 1960s. A happy clown     4     (choose) by McDonald's to appear in its advertisements. Today, as we know, that company mascot (吉祥物)， Ronald McDonald, is world famous.

However, the image of a happy clown is largely an American creation. In other cultures, the clown character is not     5     (necessary) good. One example is “Mr. Punch”, who was popular in British and French theaters during the 1700s. While Mr. Punch was funny, he was also violent, often     6     (hit) his wife during the show,     7     gave rise to the name of “bad clowns”. Even today, in the eyes of some people, clowns are evil (邪恶的)and     8     (frighten).

Of course, there are different voices. Some people think clowns are positive, creative and imaginative. They bring people     9     (please) and laughter. That's     10     attracts people, especially children, to clowns. They believe that as long as there are children in the world, there will be a future for clowns.

The Dujiangyan is the oldest man-made water system in the world, and a wonder in the development of Chinese agriculture.     1     （build）over 2,200 years ago in what is now Sichuan Province in Southwest China, this amazing engineering     2    （achieve）is still used today.

In ancient times, the region where Dujiangyan now stands     3    （suffer）from regular floods from the Minjiang River.     4    （help）the victims of the flooding, Li Bing,     5     region governor, together with his son, decided to find a solution. Li designed a series of channels built at different levels along Mount Yulei that would take away the floodwaters while leaving the river flowing naturally.     6    （good）still, the extra water could be directed to the dry Chengdu Plain, making     7     suitable for farming.

Once the system     8    （finish）, no more floods happened and the people were able to live     9    （peaceful）. Today, Dujiangyan is admired by scientists from around the world because of one feature. Unlike modern dams,     10     the water is blocked with a huge wall, Dujiangyan still lets waterflow through the Minjiang River naturally, making the ecosystem（生态系统）and fish populations exist in peace.

Plovdiv is situated in south-central Bulgaria on the two banks of the Maritsa River. The city has historically developed on seven hills, some of     1     are 250m (820.21 ft) high. Because of these hills, Plovdiv is     2    (typical) referred to in Bulgaria as “The city of the Seven Hills”. Plovdiv’s history     3    (date) back to 6000 BC. Though originally it was     4    Thracian city, Plovidiv has been ruled by many empires over centuries. Later it       5    (conquer) by the Romans. Only in 1885 did the city become part of Bulgaria. Nowadays it’s the second     6    (large) city in Bulgaria and it’s a significant economic, educational and cultural center.

Plovdiv remains a popular     7    (choose) for vacation travel. I have been obsessed with the city     8    years. Last summer I was lucky     9    (spend) a couple of days in this city and I just fell in love with its narrow paved streets and neat beautiful house! The Old Town is definitely worthy     10    (see). It is overwhelmed with restaurants, workshops and museums that were previously famous houses.

In human history, many ancient and splendid civilizations were born and died. China is the only country     1     uninterrupted human civilization. Chinese civilization was born on the shores of the Yellow River. And the rich land     2     Chinese civilization began is Henan Province.

The Yellow River goes across     3     (center) Henan. It is China's main north­to­south and east­to­west artery(干线)．China's most ancient tribal     4     (lead), the Yellow Emperor and the Yan Emperor, were born here. Even today, Chinese people all over the world still     5     (proud) call themselves the descendants(后裔) of these two emperors.

The river holds     6     unshakable position in the heart of every Chinese,     7     (respect) by every generation and called “the Mother River”. With intelligence, hard work and determination, Chinese descendants pursue co­existence and common prosperity on this land. The 5,464­km­long Yellow River breaks the last barrier and flows into the broad plain,     8     (form) the cradle(摇篮) of Chinese civilization.

Till now, the Yellow River     9     (raise) 13 dynasties' capital Luoyang, 8 dynasties' capital Kaifeng and the biggest economic center in     10     (it) area—Zhengzhou.

Dujiangyan is the oldest man-made water system in the world, and a wonder in the development of Chinese science.     1    (build) over 2, 200 years ago in what is now Sichuan Province in Southwest China, this amazing engineering     2    (achieve) is still used today.

In ancient times, the region in which Dujiangyan now stands     3    (suffer) from regular floods caused by overflow from the Minjiang River.     4    (help) the victims of the flooding, Li Bing, the region governor, together with his son, decided to find a solution. Li designed a series of channels built at different levels along Mount Yulei that would take away the floodwater while leaving the river flowing naturally.     5    (good) still, the extra water could be directed to the dry Chengdu Plain, making     6     suitable for farming.

Once the system was finished, no more floods occurred and the people were able to live     7    (peaceful). Today, Dujiangyan is admired by scientists from around the world because of one feature. Unlike modern dams     8     the water is blocked with a huge wall, Dujiangyan still lets water flow through the Minjiang River naturally,     9     (enable) ecosystem(生态系统) and fish populations to exist     10     harmony.