51. What have past behavioural studies found about our brain?
- A. Its capacity actually knows no limits.
- B. It grows sophisticated with practice.
- C. It keeps our most precious memories until life's end.
- D. New information learned pushes old information out.
答案：D
答案句：Previous behavioural studies have shown that learning new information can lead to forgetting. But in a new study, researchers demonstrated for the first time how this effect occurs in the brain.
参考译文：之前的行为研究表明，学习新信息会导致遗忘。但在一项新研究中，研究人员首次证明了这种效应在大脑中是如何发生的。
定位线索：题干“past behavioural studies”→答案句“Previous behavioural studies”；文中“learning new information can lead to forgetting”对应选项D“New information learned pushes old information out”。
解析：题干问过去行为研究的发现，答案句直接指出“学习新信息会导致遗忘”，即新信息会挤出旧信息，对应D选项。A选项“容量无限”是文章开头提出的问题，但并非行为研究的发现；C选项“保留最珍贵记忆”是文章首句的比喻，非研究结论；B选项“大脑随练习变得复杂”是文章第二段的观点，非行为研究内容。
52. What is the benefit of forgetting?
- A. It frees us from painful memories.
- B. It helps slow down our aging process.
- C. It facilitates our access to relevant information.
- D. It prevents old information from forming associations.
答案：C
答案句：In daily life, forgetting actually has clear advantages. Imagine, for instance, that you lost your bank card. The new card you receive will come with a new personal identificatipn number (PIN). Each time you remember the new PIN, you gradually forget the old one. This process improves access to relevant information, without old memories interfering.
参考译文：在日常生活中，遗忘实际上有明显的优势。例如，想象你丢失了银行卡。你收到的新卡会有一个新的个人识别码（PIN）。每次你记住新的PIN，你就会逐渐忘记旧的。这个过程提高了对相关信息的获取，而不会受到旧记忆的干扰。
定位线索：题干“benefit of forgetting”→答案句“forgetting actually has clear advantages”；文中“improves access to relevant information”对应选项C“facilitates our access to relevant information”。
解析：题干问遗忘的好处，答案句明确指出遗忘“提高对相关信息的获取”，即C选项的同义转述。A选项“摆脱痛苦记忆”在文中未提及；B选项“减缓衰老”无中生有；D选项“防止旧信息形成关联”与原文“without old memories interfering”意思相反，原文是防止干扰而非防止关联。
54. What do people find about their rare ability to remember every detail of their life?
- A. It adds to the burden of their memory.
- B. It makes their life more complicated.
- C. It contributes to their success in life.
- D. It constitutes a rare object of envy.
答案：A
答案句：A very small number of people are able to remember almost every detail of their life. While it may sound like an advantage to many, people with this rare condition often find their unusual ability burdensome.
参考译文：极少数人能够记住生活中几乎每一个细节。虽然对许多人来说这听起来像是一种优势，但患有这种罕见状况的人常常发现他们不寻常的能力是一种负担。
定位线索：题干“rare ability to remember every detail”→答案句“able to remember almost every detail”；文中“burdensome”对应选项A“adds to the burden”。
解析：题干问人们对这种罕见能力的感受，答案句指出“他们发现这种能力是负担”，即A选项“增加了他们的记忆负担”。A选项“使生活更复杂”是负担的引申，但B更直接；C选项“有助于成功”与原文相反；D选项“令人羡慕”是多数人的看法，而非患者自身感受。
55. What does the passage say about forgetting?
- A. It can enlarge our brain capacity.
- B. It helps get rid of negative memories.
- C. It is a way of organising our memories.
- D. It should not cause any alarm in any way.
答案：C
答案句：In a sense, forgetting is our brain's way of sorting memories, so the most relevant memories are ready for retrieval. Normal forgetting may even be a safety mechanism to ensure our brain doesn't become too full.
参考译文：从某种意义上说，遗忘是我们大脑整理记忆的方式，以便最相关的记忆随时可以检索。正常遗忘甚至可能是一种安全机制，以确保我们的大脑不会变得太满。
定位线索：题干“what does the passage say about forgetting”→答案句“forgetting is our brain's way of sorting memories”；文中“sorting memories”对应选项C“a way of organising our memories”。
解析：题干问文章关于遗忘的说法，答案句明确指出“遗忘是大脑整理记忆的方式”，即A选项“组织记忆的方式”。B选项“扩大大脑容量”是文章最后一句的引申，但原文说的是“防止太满”而非扩大；C选项“摆脱负面记忆”无中生有；D选项“不应引起任何警觉”在文中未提及。