题目内容：

任务型阅读（每空一词）

Trees are one of the oldest citizens (公民) of our earth．Just like us, trees change a lot when they grow．At one to three years old, young trees learn how to protect themselves. For example，many trees grow thorns (刺) to tell animals not to go near．Most young trees have large, deep green leaves so that they can catch enough sunlight and change it into their food and energy．

When trees are 4 years old, they begin to grow very fast and become strong enough to face challenges     (挑战) in life．At the age of l5, trees become young adults(成人). They grow more slowly and begin to produce (生产) flowers and fruit．

It is not until the trees are 20 to 25 years old that they become real adults. The trees reach their largest sizes．Adult trees give us many things such as oxygen(氧气)and natural beauty．If we give them good care，they will go on to live healthily for many years．

As time goes on，trees begin to grow older and older and even die．At this time，they still have their important place in nature．In many ways，the life of trees is like our own life experience. Enjoy every minute of the life of the trees and take care of them!

Title： The life of trees
91.1.	Growing	Things they can do
1～3	Growing thorns； Having 1arge, deep green leaves	Learn to protect themselves； Catch enough 92.2. and change it into their food and 93.3.
4	Growing very fast； Becoming strong enough	Face challenges in life
15	Becoming young adults； 94.4. more slowly	Produce flowers and fruit
20～25	Becoming real adults； Reaching their largest sizes	Give people many things 95.5.oxygen and natural beauty