51. What do we learn from the passage about an enzyme scientists have created?
- A. It was identified during a lab experiment accident.
- B. It may make full recycling of plastic bottles a reality.
- C. It was a breakthrough made with persistent efforts.
- D. It may initiate a radical reform in plastic industry.
答案：B
答案句：Scientists have created by accident an enzyme ( 酶 )that breaks down plastic drinks bottles. The breakthrough could help solve the global plastic pollution crisis by enabling for the first time the full recycling of bottles.
参考译文：科学家们意外地创造出一种能分解塑料饮料瓶的酶。这一突破可能有助于解决全球塑料污染危机，因为它首次实现了瓶子的完全回收。
定位线索：题干“enzyme scientists have created”对应答案句“Scientists have created by accident an enzyme”；文中“enabling for the first time the full recycling of bottles”对应选项B“may make full recycling of plastic bottles a reality”。
解析：题干问关于科学家创造的酶我们了解到什么。答案句直接说明该酶是意外创造的，且能实现瓶子的完全回收，与选项B“可能使塑料瓶的完全回收成为现实”同义对应。选项A“在实验室实验事故中被发现”偷换概念，原文是“by accident”指偶然，并非“事故”；选项C“经过持续努力”与原文“by accident”矛盾；选项D“引发塑料行业彻底改革”范围过大，原文未提及。
52. What does the passage say about the bug that produces the important enzyme?
- A. It has a natural ability to consume plastics.
- B. It is a bacterium that reproduces at a high rate.
- C. It is essential to the recycling of plastic bottles.
- D. It has a chemical structure unknown to scientists.
答案：A
答案句：The new research was spurred by the discovery in 2016 of the first bacterium that had naturally evolved to eat plastic at a waste dump in Japan.
参考译文：这项新研究是由2016年在日本一个垃圾场发现的第一个自然进化出吃塑料能力的细菌所推动的。
定位线索：题干“the bug that produces the important enzyme”对应答案句“the first bacterium that had naturally evolved to eat plastic”；文中“naturally evolved to eat plastic”对应选项A“has a natural ability to consume plastics”。
解析：题干问关于产生重要酶的细菌，文章说了什么。答案句明确指出该细菌“自然进化出吃塑料的能力”，与选项A“具有天然的消耗塑料的能力”同义。选项B“以高速率繁殖”无中生有；选项C“对塑料瓶回收至关重要”范围扩大，原文只说该细菌启发研究；选项D“化学结构未知”与原文“revealed the detailed structure”矛盾。
54. What does Prof. McGeehan say about the recycling of plastic bottles?
- A. Manufacturers are implementing it on an increasingly larger scale.
- B. It generates huge business opportunities for plastic manufacturers.
- C. It has aroused persistent interest among the general public.
- D. Manufacturers are beginning to explore ways of doing it.
答案：D
答案句：“It is so easy for manufacturers to generate more of that stuff, rather than even try to recycle, but I believe there is a public interest here: perception is changing so much that companies are starting to look at how they can properly recycle these bottles.”
参考译文：“制造商很容易生产更多那种东西，而不是尝试回收，但我相信这里有公共利益：观念正在发生巨大变化，公司开始研究如何正确回收这些瓶子。”
定位线索：题干“Prof. McGeehan say about the recycling of plastic bottles”对应答案句“companies are starting to look at how they can properly recycle these bottles”；文中“companies are starting to look at”对应选项D“Manufacturers are beginning to explore ways of doing it”。
解析：题干问麦吉汉教授关于塑料瓶回收的说法。答案句明确说“公司开始研究如何正确回收这些瓶子”，与选项D“制造商开始探索回收的方法”同义。选项A“制造商正以越来越大的规模实施”无中生有；选项B“为塑料制造商带来巨大商机”无中生有；选项C“引起公众持续兴趣”偷换概念，原文说“观念正在改变”，并非“持续兴趣”。
55. What is Prof. AdisaAzapagic's advice concerning the application of the enzyme?
- A. Developing technologies to address greenhouse gas emissions.
- B. Considering the extra cost involved in producing the enzyme.
- C. Assessing its possible negative impact on the environment.
- D. Studying the full life cycle of the enzyme as the first step.
答案：C
答案句：Prof. Adisa Azapagic, at the University of Manchester in the UK, agreed the enzyme could be useful but added:“A full life-cycle assessment would be needed to ensure that the technology does not solve one environmental problem-waste-at the expense of others, including additional greenhouse gas emissions.”
参考译文：英国曼彻斯特大学的阿迪萨·阿扎帕吉奇教授同意这种酶可能有用，但补充说：“需要进行全面的生命周期评估，以确保这项技术不会以牺牲其他环境问题（包括额外的温室气体排放）为代价来解决一个环境问题——废物。”
定位线索：题干“Prof. AdisaAzapagic's advice”对应答案句“A full life-cycle assessment would be needed”；文中“ensure that the technology does not solve one environmental problem at the expense of others”对应选项C“Assessing its possible negative impact on the environment”。
解析：题干问阿扎帕吉奇教授关于酶应用的建议。答案句明确说需要“全面的生命周期评估”以确保技术不会以牺牲其他环境问题为代价，即评估其潜在的负面影响，与选项C对应。选项A“开发技术解决温室气体排放”偷换概念，原文是评估而非开发；选项B“考虑生产酶的额外成本”无中生有；选项D“首先研究酶的完整生命周期”偷换概念，原文是“生命周期评估”而非“研究生命周期”。