As we all know, the Great Wall of China is one of the greatest     1     (sight) in the world---the longest wall in the world ,which     2     (consider) the symbol of China and the wisdom of Chinese people.

With     3    long history of more than 2300 years, the “Long Wall” was built in different areas by different dynasties     4     (protect) their territorial（领土的）borders. During the construction of the Great Wall, there were many     5     (interest) legends and stories, such as Meng Jiang Nü weeping over the Great Wall, a sad     6     romantic love story .

Today, the Great Wall has become a place     7     interest not only to the Chinese but also to people all over the world. Perhaps the most     8     (wide) famous advertising words in history come from the poetic pen of Chairman Mao: “He     9     has never been to the Great Wall is not a true man,” Actually, since the Great Wall was opened to the public, hundreds of millions of visitors     10     (be) to its various sections.

As settlers moved to California     1     the mid-nineteenth century, they became concerned about the lack of rapid     2     (communicate) with the eastern United States. Because of the dangers and hardships of     3     (cross) the West, mail often did not arrive. Therefore the most important mails     4     (send) via Panama,     5     took a month or more. In 1860 a stagecoach company decided to meet the problem by beginning the Pony Express. The company hired     6    bravest riders and bought the fastest horses     7     (use) as relay(替换) teams between Missouri and California, and the company promised     8    mails would be sent in ten days. The company established two hundred stations along the route at which riders could rest and change horses. In less than two years,     9     , telegraph lines were completed and the Pony Express was     10     longer needed.