发布时间 : 星期一 文章2017年6月英语四级考试真题及答案解析版（第3套）更新完毕开始阅读17bdc5f2db38376baf1ffc4ffe4733687f21fc4a
【答案】C
【解析】根据题干关键词Millennials和buy a house可定位第四段。 49. What might hinder real estate development in the U.S.? A) The continuing economic recession in the country. B) The lack of confidence on the part of investors. C) The fierce global competition. D) The worsening infrastructure. 【答案】D
【解析】根据题干关键词hinder和real estate development可定位至第六、七段。 50. How do most of the respondents in the survey feel about the U.S. real-estate market in 2015?
A) Pessimistic. B) Hopeful. C) Cautious. D) Uncertain. 【答案】B
【解析】根据题干关键词respondents和real-estate market in 2015可定位至第八段。
Passage Two
Questions 51 to 55 are based on the following passage.
The brain is truly a marvel. A seemingly endless library, whose shelves house our most precious memories as well as our lifetime’s knowledge. But is there a point where it reaches capacity? In other words, can the brain be “full”？
The answer is a resounding no, because, well, brains are more sophisticated than that. A study published in Nature Neuroscience earlier this year shows that instead of just crowding in, old information is sometimes pushed out of the brain for new memories to form.
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.
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 identification 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.
And most of us will be able to identify with the frustration of having old memories interfere with new, relevant memories. Consider trying to remember where
you parked your car in the same car park you were at a week earlier. This type of memory (where you are trying to remember new, but similar information) is particularly susceptible to interference.
When we acquire new information, the brain automatically tries to incorporate it within existing information by forming associations. And when we retrieve information, both the desired and associated but irrelevant information is recalled. The majority of previous research has focused on how we learn and remember new information. But current studies are beginning to place greater emphasis on the conditions under which we forget, as its importance begins to be more appreciated. 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.
Some report an inability to think about the present or the future, because of the feeling of constantly living in the past, caught in their memories. And this is what we all might experience if our brains didn’t have a mechanism for superseding information that’s no longer relevant and did indeed fill up.
At the other end of the spectrum is a phenomenon called “accelerated long-term forgetting”，which has been observed in epilepsy and stroke patients. As the name suggests, these people forget newly learnt information at a much faster rate, sometimes within a few hours, compared to what’s considered normal.
It’s believed this represents a failure to “consolidate” or transfer new memories into long-term memory. But the processes and impact of this form of forgetting are still largely unexplored.
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.
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
【解析】根据题干中的关键词past behavioural studies可定位至第三段。 52. What is the benefit of forgetting? A) It frees us from painful memories. B) It helps slow down our aging process.