Probably you have seen photos of the Grand Canyon（峡谷）, the great valley in the desert country of Arizona. But you must go there yourself to feel its true size and beauty. The Grand Canyon is one of the greatest natural wonders of the world
The Colorado River formed the Grand Canyon over millions of years. Slowly, the river cut down through hard rock. At the same time, the land was rising. Today the canyon is 1.5 kilometers and 445 kilometers long. The oldest rocks at the bottom of the canyon are more than 1 billion years old. The width varies from about 200 meters to 29 kilometers across. The rim or top of the canyon is about 2,300 meters above sea level on the South Rim, and about 3,000 meters on the other side. As a result, there are different kinds of plants and animals on opposite sides of the canyon. The South Rim is dry desert country. The North Rim has tall forests.
The canyon looks different at different times of day, and in different seasons and weather. At sunrise and sunset the red, gold, brown and orange colors of the rocks are especially clear and bright. In winter, the canyon is partly covered with snow.
The view from the South Rim of the Grand Canyon is the best. Most visitors come here and stay in campgrounds or hotels. Every point along the canyon’s edge offers a different view.
The North rim of the Canyon is quieter. It takes all day to drive there from the South Rim because there is only one bridge across the Colorado River. On the way, you go through Navado Indian lands, and a colorful pink desert called “The Painted Desert”.
11. The best way to feel the true beauty of the Grand Canyon is to________.
A. see its photographs            B. listen to the report about it
C. watch its introduction on TV    D. go there yourself and visit it
12. According to the second paragraph, ________.
the Grand Canyon has a short history      
B. its size never changed in the history
C. the Grand Canyon was formed by the earthquake 
D. You can enjoy different scenery on different sides of the canyon
13. The scene the canyon is ________.
various depending on different time and places
the same    
various depending on different time
various depending on different places
14. If you want to visit the North Rim from the South Rim, you________.
can go there in many directions
won’t spend much time on the way
can visit The painted Desert on the way
needn’t go across any bridges
15. If you want to have a visit to the Grand Canyon, you’d better go to _______.
A. the North Rim                  B. the South Rim
C. the bottom                     D. Navado Indian Lands