Question

【题目】Humans have long been interested greatly in the idea of being able to walk on water. Sadly, biological facts prevent us ever realizing this dream without artificial aid—we simply weigh too much, and all our weight pushes down through our relatively small feet, resulting in a lot of pressure that makes us sink.

However, several types of animals can walk on water. One of the most interesting is the common basilisk Basilicus basilicus, a lizard (蜥蜴) native to Central and South America. It can run across water for a distance of several meters, avoiding getting wet by rapidly hitting the water's surface with its feet. The lizard will reach a speed of 20 steps per second to keep moving forward. For humans, we would need huge feet that we could bring up to our ears in order to create enough “hitting”.

But fortunately there is an alternative: cornflour(玉米淀粉). By adding enough of this common thickening agent to water (and it does take a lot), you can create a special mixture that doesn't behave like normal water. Now, if the surface of the water is hit hard enough, particles(微粒) in the water get together for a moment to make the surface hard. Move quickly enough and put enough force into each step, and you really can walk across the surface of this adequately thick liquid of cornflour.

Fun though all this may sound, it's still rather messy and better read about in theory than carried out in practice. If you must do it, then keep the water wings(救生圈) ready in case you start to sink—and take a bath afterward!

【1】Walking on water hasn't become a reality mainly because humans _________.

A. are not interested in it

B. are afraid to make an attempt

C. have not invented proper tools

D. have biological limitations

【2】What do we know about Basilicus basilicus from the passage?

A. It is light enough to walk on water.

B. It can run across water at a certain speed.

C. Its huge feet make it able to stay above water.

D. Its unique skin keeps it from getting wet in water.

【3】What is the function of the cornflour according to the passage?

A. To help the liquid behave normally.

B. To turn the water into solid.

C. To create a thick liquid.

D. To make the water move rapidly.

【4】What is the author’s attitude toward the idea of humans’ walking on water?

A. It is risky but beneficial.

B. It is impractical though possible in thoery.

C. It is crazy and cannot become a reality.

D. It is interesting and worth trying.

Answer 1

【答案】

【1】D

【2】B

【3】C

【4】B

【解析】

试题分析：本文为说明文。水上行走一直是人类的梦想，但由于身体的局限性很难完成，但现在有一种折中的方法——在水面上撒玉米粉。

【1】D 细节理解题。根据第一段第二句话可知，因为我们太重了，如果没有人工辅助，我们很难在受伤行走，也就是有身体的限制。故选D。

【2】B 细节理解题。根据第二段第二句和第三句话可知，这种蜥蜴每秒移动二十步来保持高速水上行走，故选B。

【3】C 细节理解题。根据第三段可知，把足够的玉米粉撒在水面上，水中的粒子群可以使水面变得坚固一些，只要速度够快，每一步都用力均匀就能走过水面，故选C。

【4】B 推理判断题。根据第四段可知，利用玉米面在水面上行走听起来不错，但在实践时有一定危险，一定要做好防护措施，故选B。