第二节 阅读填空（每小题1分，共5分）
Deserts are areas with very little rain. They are hot and dry most of the time.
51. There are some reasons.
One reason is the weather. Deserts are often found near the tropics. Here the sunlight is very strong. 52. Hot air rises, and then dry air sinks(下沉) over the desert areas. This dry air gets warmer and stops rain from falling.
53. In some places, strong winds blow all the time. These winds can carry away the topsoil, the layer of the ground where plants grow. Without topsoil, plants can't grow, and the land becomes a desert.
Sometimes, people also cause deserts. When we cut down too many trees, the land can turn into a desert. 54. Without trees, the ground gets dry and turns into sand.
Deserts are important too. They are home to special plants and animals that are used to living in hot, dry places. 55.
A. This makes air very hot.
B. Another reason is wind.
C. How does an area become a desert?
D. Trees help keep water in the ground.
E. But we should be careful not to make more deserts.

51. C 52. A 53. B 54. D 55. E

【分析】本题为阅读填空题，需结合上下文语境及逻辑关系匹配选项。首先通读全文，明确文章围绕沙漠形成的原因及沙漠的重要性展开：51空后提到“有一些原因”，说明前文是提出沙漠形成的问题，对应选项C；52空前说阳光强烈，后文讲热空气上升，中间需衔接阳光带来的结果，对应选项A；53空后讲风对沙漠形成的影响，说明此处是另一个原因，对应选项B；54空前讲砍树，后文说无树的后果，需说明树的作用，对应选项D；55空前说沙漠重要，后文转折提出注意事项，对应选项E。
【解析】51空：后文“There are some reasons.”表明前文是询问沙漠形成的问题，选项C“How does an area become a desert?”符合语境；52空：前文“the sunlight is very strong”与后文“Hot air rises”衔接，选项A“This makes air very hot.”是阳光强的结果，符合逻辑；53空：前文讲天气原因，后文讲风的影响，选项B“Another reason is wind.”引出风的原因，符合段落结构；54空：前文“cut down too many trees”与后文“Without trees”衔接，选项D“Trees help keep water in the ground.”说明树的作用，符合语境；55空：前文讲沙漠重要，选项E“But we should be careful not to make more deserts.”转折提出注意事项，符合逻辑。
【答案】51.C 52.A 53.B 54.D 55.E
【知识点】阅读理解（七选五）、语篇逻辑推理
【点评】本题考查学生对语篇上下文逻辑关系的理解能力，需通过前后文的关键词、句子含义匹配选项，难度适中，是初中英语常见题型，学生只要理清段落结构和句子间的联系即可正确作答。
【难度系数】0.6