C
Young trees don’t just grow；they develop a personality and learn more about their environment and how they should best behave in it.They also help each other out whenever there’s trouble.
Personality, just as among people, varies among trees.Some are anxious, some bold.On the author’s land, there are three oak trees growing close together.One of the oak trees always starts to shed its leaves two weeks earlier than the others.Since they all experience the same temperature, the same soil and the same length of day, such variables can’t be the explanation.So what’s happening？Well, this tree is simply more careful than the others.Whoever holds on to their leaves longer can do more photosynthesis(光合作用) and store more nutrients.However, the longer a tree keeps its leaves, the higher the risk of injury.
Not only do trees make their own decisions, they also learn from their mistakes.A tree, for example，keeping its leaves too long during one year will never make this mistake again.This leads to several other conclusions：trees must notice the temperature and the length of the day and be able to save their experiences somewhere.Obviously, trees don’t have brains, but it is thought that in the sensitive tips of their roots they keep track of information and experiences.
But trees aren’t only clever when it comes to caring for themselves.They also support each other whenever there’s trouble by giving warnings and even taking care of sick and weak conspecifics with nutrients.For example, one time the author found a very old tree stump.Its insides had rotted a long time ago to topsoil.But the wood on the outside of the stump was still living.How was this possible？Well, the stump was nourished by its neighbors with nutrients from the root system, and had been for at least 400 years!
Why do trees do_such_a_thing？It’s simple: it’s better together.Trees need the forest; it protects them from storms, provides the right microclimate and warns them of attacks.
28．Why does the author mention the three oak trees?
A．To illustrate trees can learn from experiences.
B．To show trees can make independent decisions.
C．To explain trees are quite supportive to each other.
D．To prove trees have the same personalities as humans.
29．According to the text, which of the following best describes general features of trees?
A．Anxious and bold.
B．Smart and adventurous.
C．Helpful and wellbehaved.
D．Adaptable and supportive.
30．What does the underlined phrase “do such a thing” mean?
A．Give warnings.
B．Offer assistance.
C．Depend on others.
D．Provide nutrients.
31．Where does this text most probably come from?
A．A public lecture.
B．A science book.
C．An experiment report.
D．A travel journal.
【解题导语】 本文是一篇说明文，主要介绍了树的智慧：每棵树都有它不同的个性，遇到困难时它们也会互相帮助；研究发现，树不但能自己做决定，还能从自己的错误中吸取教训。
28．B 解析：推理判断题。根据第二段第四句“One of the oak trees always starts to shed its leaves two weeks earlier than the others.”可知，三棵橡树中，有一棵总比其他两棵先落叶；结合第三段第一句“Not only do trees make their own decisions, they also learn from their mistakes.”可知，树木能自己做决定；据此可推知，作者提及三棵橡树旨在说明树木可以自己做决定，故B项正确。
29．D 解析：推理判断题。根据第三段第一句“Not only do trees make their own decisions, they also learn from their mistakes.”，并结合第三段的内容可知，树木不仅能自己做决定，还能从自己的错误中吸取教训；据此可推知，树木适应能力强；根据第四段第一、二句“But trees aren’t only clever when it comes to caring for themselves.They also support each other whenever there’s trouble by giving warnings and even taking care of sick and weak conspecifics with nutrients.”可知，树木不仅善于照顾自己，当遇到困难时，它们会发出警告，相互支持，甚至照顾生病、虚弱的同类；据此可推知，树木之间互帮互助，故D项正确。
30．B 解析：词义猜测题。根据第四段尾句“Well, the stump was nourished by its neighbors with nutrients from the root system, and had been for at least 400 years！”可知，树桩是由它的邻居从根处给予营养来滋养的；结合第五段第一句“Why do trees do_such_a_thing？”和第五段的内容可知，该处表示“为什么树木要互相帮助？”，故画线短语是指提供帮助，故B项正确。
31．B 解析：文章出处题。通读全文可知，本文是一篇说明文，主要介绍了树的智慧：每棵树都有它不同的个性，遇到困难时它们也会互相帮助；研究发现，树不但能自己做决定，还能从自己的错误中吸取教训；据此可推知，本文最可能选自科学书籍，故B项正确。
Young trees don’t just grow；they develop a personality and learn more about their environment and how they should best behave in it.They also help each other out whenever there’s trouble.
Personality, just as among people, varies among trees.Some are anxious, some bold.On the author’s land, there are three oak trees growing close together.One of the oak trees always starts to shed its leaves two weeks earlier than the others.Since they all experience the same temperature, the same soil and the same length of day, such variables can’t be the explanation.So what’s happening？Well, this tree is simply more careful than the others.Whoever holds on to their leaves longer can do more photosynthesis(光合作用) and store more nutrients.However, the longer a tree keeps its leaves, the higher the risk of injury.
Not only do trees make their own decisions, they also learn from their mistakes.A tree, for example，keeping its leaves too long during one year will never make this mistake again.This leads to several other conclusions：trees must notice the temperature and the length of the day and be able to save their experiences somewhere.Obviously, trees don’t have brains, but it is thought that in the sensitive tips of their roots they keep track of information and experiences.
But trees aren’t only clever when it comes to caring for themselves.They also support each other whenever there’s trouble by giving warnings and even taking care of sick and weak conspecifics with nutrients.For example, one time the author found a very old tree stump.Its insides had rotted a long time ago to topsoil.But the wood on the outside of the stump was still living.How was this possible？Well, the stump was nourished by its neighbors with nutrients from the root system, and had been for at least 400 years!
Why do trees do_such_a_thing？It’s simple: it’s better together.Trees need the forest; it protects them from storms, provides the right microclimate and warns them of attacks.
28．Why does the author mention the three oak trees?
A．To illustrate trees can learn from experiences.
B．To show trees can make independent decisions.
C．To explain trees are quite supportive to each other.
D．To prove trees have the same personalities as humans.
29．According to the text, which of the following best describes general features of trees?
A．Anxious and bold.
B．Smart and adventurous.
C．Helpful and wellbehaved.
D．Adaptable and supportive.
30．What does the underlined phrase “do such a thing” mean?
A．Give warnings.
B．Offer assistance.
C．Depend on others.
D．Provide nutrients.
31．Where does this text most probably come from?
A．A public lecture.
B．A science book.
C．An experiment report.
D．A travel journal.
【解题导语】 本文是一篇说明文，主要介绍了树的智慧：每棵树都有它不同的个性，遇到困难时它们也会互相帮助；研究发现，树不但能自己做决定，还能从自己的错误中吸取教训。
28．B 解析：推理判断题。根据第二段第四句“One of the oak trees always starts to shed its leaves two weeks earlier than the others.”可知，三棵橡树中，有一棵总比其他两棵先落叶；结合第三段第一句“Not only do trees make their own decisions, they also learn from their mistakes.”可知，树木能自己做决定；据此可推知，作者提及三棵橡树旨在说明树木可以自己做决定，故B项正确。
29．D 解析：推理判断题。根据第三段第一句“Not only do trees make their own decisions, they also learn from their mistakes.”，并结合第三段的内容可知，树木不仅能自己做决定，还能从自己的错误中吸取教训；据此可推知，树木适应能力强；根据第四段第一、二句“But trees aren’t only clever when it comes to caring for themselves.They also support each other whenever there’s trouble by giving warnings and even taking care of sick and weak conspecifics with nutrients.”可知，树木不仅善于照顾自己，当遇到困难时，它们会发出警告，相互支持，甚至照顾生病、虚弱的同类；据此可推知，树木之间互帮互助，故D项正确。
30．B 解析：词义猜测题。根据第四段尾句“Well, the stump was nourished by its neighbors with nutrients from the root system, and had been for at least 400 years！”可知，树桩是由它的邻居从根处给予营养来滋养的；结合第五段第一句“Why do trees do_such_a_thing？”和第五段的内容可知，该处表示“为什么树木要互相帮助？”，故画线短语是指提供帮助，故B项正确。
31．B 解析：文章出处题。通读全文可知，本文是一篇说明文，主要介绍了树的智慧：每棵树都有它不同的个性，遇到困难时它们也会互相帮助；研究发现，树不但能自己做决定，还能从自己的错误中吸取教训；据此可推知，本文最可能选自科学书籍，故B项正确。
