大家帮忙讨论一个阅读理解题,谢谢了
Questions 1 to 5 are based on the following passage.
　　The Nile made Egypt’s civilization possible. The river is more than 400 miles long. In its fertile valley crops are grown for food and cotton for clothing. Mud from the river bottom makes good bricks for houses. Thus ways of getting food, clothing and shelter were close for the Egyptians.
　　The Nile is a highway for the people of Egypt. Flat bottomed boats and large narrow barges carry products from one city to another. There are also passenger boats on the Nile, carrying people up and down the river. In ancient times huge blocks of stones were floated down the river on barges. These stones are used in making buildings and monuments.
　　For thousands of years the Egyptians have depended on the Nile for their crops. The land on both sides of the Nile is desert, where crops cannot be raised
　　But crops grow well in the Nile Valley. In fact, several different crops are often grown on the same land during the same year.
　　Once the Nile flooded each year, overflowed its banks, and carried rich soil in land every summer. These floods were caused by early summer rains.
　　At present there is a series of dams in the Nile. Water raises high in the river each summer as usual. The people do not let the Nile flood, however. They store the water behind dams. It is now possible to use the water as needed, not just at flood time.
　　1. In the past ______.
　　A. there was rain all the year long
　　B. the Nile flooded every year
　　C. the Nile became deeper and deeper after each rainfall
　　D. the Nile was not a long river
　　2. Egyptians have grown crops well ______.
　　A. on both sides of the Nile
　　B. on the land near the desert area
　　C. in the Nile valley
　　D. far away from the desert area
　　3. In the valley of the Nile ______.
　　A. bricks for houses are made
　　B. different crops are raised on the same land
　　C. only cotton can grow well
　　D. people grow all crops except cotton
　　4. “The Nile is a highway for the people of Egypt” means ______.
　　A. cars and trucks can move as fast as possible along it
　　B. the river bottom can serve as a road in dry season
　　C. the river is an important water transportation line in Egypt
　　D. on the river there are a lot of boats and people
　　5. Which of the following can best summarize the passage?
　　A. The Nile is the source of flood.
　　B. The Nile is a highway for the people in Egypt.
　　C. The flat bottomed boats have been used.
　　D. The Nile made Egypt’s civilization possible.
这是我做的答案：1.D2.C 3.B 4.C 5.B 是不是全对呀,能不能给个详细的分析谢谢啦