Question

15．American scientists have developed the first material that repairs itself．The material is a form of plastic that has been engineered to fill breaks in its surface．
Plastics are used today in everything．Scientists wanted to find a way to make objects made of plastic last longer．The researchers hope their new discovery can be used to make objects that are difficult or impossible to replace．
The surface of plastic objects breaks over time．Very small breaks develop every time a plastic object is used．The researchers wanted to find out how to stop plastic from developing small breaks that weaken and destroy it．They found the answer in the chemical structure of plastic itself．The research team found a way to make plastic that contains very small balloons filled with monomer（单体） liquid．When the new plastic cracks，the monomer liquid is let out and flows into the crack．Thus the break is repaired．The repaired plastic has seventy-five percent of the strength of undamaged plastic．
The new self-repairing plastic is not yet ready for production．But it has several possible uses．One could be in space vehicles where parts cannot be repaired or replaced．Another possible use might be in bridges．And it could be used in people，to replace bone joints that have become broken or damaged．
33．The passage mainly talks aboutA．
A．plastic that repairs itself               
B．the chemical structure of plastic
C．permanent material invented           
D．small balloons that makes plastic stronger
34．We know from the passage that the repair is done asB．
A．the cracked plastic parts are changed    
B．the plastic cracks
C．the liquid is put into the plastic cracks    
D．the plastic is made
35．The scientists are planning to use the new material in space vehicles，bridges and people becauseA．
A．the plastic parts in them are required to last longer
B．they want to experiment in these places first
C．the new material cannot be used elsewhere
D．the plastic parts in them are easily broken or damaged．

Answer 1

分析 本文是一篇科教类阅读，美国科学家已经开发出第一种材料可以自我修复，材料是塑料的一种形式，在其表面工程填补了．今天在每方面都使用塑料，科学家们想找到一种方法使塑料可以持续更长时间，塑料制成的研究人员希望他们的新发现可以被用来使之成为可能．

解答 33．答案：A．主旨大意题．根据全文内容，尤其是"American scientists have developed the first material that repairs itself．The material is a form of plastic that has been engineered to fill breaks in its surface．"可知，本文主要讲述了自我修复的塑料．故选A．
34．答案：B．细节理解题．根据"When the new plastic cracks，the monomer liquid is let out and flows into the crack．Thus the break is repaired．The repaired plastic has seventy-five percent of the strength of undamaged plastic．"可知，液体进入塑性裂缝时，修复完成．故选B．
35．答案：A．细节理解题．根据"One could be in space vehicles where parts cannot be repaired or replaced．Another possible use might be in bridges．And it could be used in people，to replace bone joints that have become broken or damaged．"可知，其中的塑料部件需要持续时间更长．故选A．

点评 本文是一篇科教类阅读，题目涉及多道细节理解题．主旨大意题．做题时学生应仔细阅读原文，把握文章主要内容，联系文章上下文内容并结合所给选项含义，从中选出正确答案，一定要做到有理有据，切忌胡乱猜测