单选题 {{B}}Passage Three{{/B}}
Trees should only be pruned (修剪) when there is a good reason for doing so. Many gardeners believe that more damage results from doing it unnecessarily than from leaving the tree to grow in its own way.
First, pruning may be done to make sure that trees have a desired shape. The object may be to get a tree of the right height, and to help the growth of small side branches which will thicken its appearance or give it a special shape. Secondly, pruning may be done to make the tree healthier. You may cut out diseased or dead wood, or branches that are rubbing against each other and thus causing wounds. A tree may grow healthier by removing the branches that are locking up the centre and so preventing the free movement of air.
One result of pruning is that an open wound is left on the tree and this provides an easy entry (进入) for diseases, but it is a wound that will heal. Often there is a race between the healing and the disease as to whether the tree will live or die. Pruning is usually clone in winter, for then you can see the shape of the tree clearly without the interference from the leaves.
单选题 According to the article, which of the following statement is NOT true?
【正确答案】 B
【答案解析】根据第一段最后一句可知该陈述是错误的，修剪只是在有必要的时候才进行。
单选题 Which of the following usually causes a tree to grow unhealthy?
【正确答案】 C
【答案解析】根据第二段A tree may grow healthier by removing the branches that are locking up the centre可知树中间的枝杈不利于树木生长，C与文章内容相反，因此错误。
单选题 The wounds result from pruning will do the following EXCEPT______.
【正确答案】 D
【答案解析】根据第三段可知A、B、C选项都被提到，只有D选项不相关。
单选题 The writer suggests that pruning should be done in winter because______.
【正确答案】 C
【答案解析】根据短文最后一句得知冬季树叶少能方便修剪树木，A、B、D皆为干扰项，与原句不符；
单选题 The writer's purpose when writing this passage is______.
【正确答案】 C
【答案解析】通过全文的介绍可知该文章讲述了修剪树木的注意事项，因此C是正确答案。