Tress should only be pruned when there is a good and clear reason for doing so and , the

Question 26 to 30 are based on the following passage .

Tress should only be pruned when there is a good and clear reason for doing so and , the number of such reasons is small . Pruning involves the cutting away of overgrown and unwanted branches , and the inexperienced gardener can be encouraged by the thought that more damage results from doing it unnecessarily than from the tree to grow in its own way .

First , pruning may be done to make sure that trees have a desired shape or size . The object may be to get a tree of the right height , and at the same time 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 heavier . You may cut out diseased or dead wood , or branches that are rubbing against each other and thus cause wounds . The health of a tree may be encouraged by removing branches that are blocking up the center 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 for disease , 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 , so that there is a period when the tree is at risk . It should be the aim of every gardener to reduce that risk of death as far as possible . It is essential to make the area , which has been pruned smooth , and clean , for healing will be slowed down by roughness . You should allow the cut surface to dry for a few hours and then paint it with one of the substances available from garden shops especially for this purpose . Pruning is usually done in winter , for then you can see the shape of the tree clearly without interference from the leaves and also it is very unlikely that the cuts you make will bleed . If this does happen , it is , of course , impossible to paint them properly .

26. Pruning should be done to _____.

A)make the tree grow taller . B) does not protect them form. the wind

C)get rid of the small branches D) make the small branches thicker .

27. Trees become unhealthy if the gardener_______

A)allows too many branches to grow in the middle

B)does not protect them from the wind

C)forces them grow too quickly

D)damages some of the small side branches.

28 . Why is a special substance painted on the tree ？

A)to make a wound smooth .

B)to prevent disease entering a wound .

C)to cover a rough surface .

D) to help a wound to dry .

29. A good gardener prunes tree ____

A) at intervals throughout the year

B) as quickly as possible

C) occasionally when necessary

D) regularly every winter

30 . What was the author’s purpose when writing this passage ？

A)to give practical instruction for pruning a tree

B)to give a gardener description of pruning

C)to explain how trees develop disease

D)to discuss different methods of pruning