单选题 Co-operation means working together for the benefit of all. Without co-operation modern society could not exist. Co-operation has been at its best among the farmers in the dry areas of certain parts of Australia and Africa. The fields have been irrigated in these areas. Crops cannot be grown without water. For this purpose, canals and reservoirs have been built. The canals have been cut through the fields of not only one farmer. Those who live higher up the valley than the others have permitted canals to be built through their land in order to carry water to the fields of farmers lower down. When there is a long period without rain, all share the water. Instead of taking all the water for them selves, the farmers in the higher land leave enough water for their neighbours down the valley. Farming in the dry areas has been made possible by such co-operation. By co-operation farmers have learned to make even the desert produce crops.

单选题 Co-operation means ______.

【正确答案】 C

【答案解析】[解析] 由文章第一句“Co-operation means working for the benefit of all”，但此处应对all正确理解，是合作的全体而不是全世界。

单选题 A reservoir is used ______.

单选题 In dry weather the farmers who live higher up the valley ______.

【正确答案】 A

【答案解析】[解析] 由“Those who live higher up the valley than the others have permitted canals to be built through their land in order to carry water to the fields of farmers lower down”可以看出他们会与邻居们共同用水。