1 . 阅读下面短文,在空白处填入1个适当的单词或括号内单词的正确形式
Rivers are one of our most important natural resources. Many of the world’s great cities are located on rivers and almost every country has at least one river 1 (flow) through it, which plays an important part in the lives of 2 (it) people.
Since the beginning of history, people 3 (use) rivers for transportation. The Yellow River and Changliang River play a large role in China. The Mississippi, the 4 (long) one in the United States ever influenced the American people 5 (great) in history. The lifeline of Egypt is the Nile. Rivers provide fresh water 6 drink, grow crops, make electricity and chances to have fun for those 7 live along their banks.
8 the cities grow in size and industries increase in number, the river water is severely being polluted. It urges all countries to make 9 (decide) and take immediate action to stop it from 10 (pollute) any more.