Trees are one of our best friends. They help keep the air clean, stop noise pollution, improve water quality and provide food and building materials.
Just like us, trees change a lot as they grow. At one to three years old, young trees learn how to protect themselves. For example, many trees grow thorns (刺) to warn animals not to go near.
When trees are four years old they begin to grow very quickly and become strong enough to face challenges later in life. At the age of 15, trees become young adults. They grow more slowly and begin to produce flowers and fruit.
The tree doesn't become a real adult until it is 20 to 25 years old. The tree reaches its largest size. Not only does the adult tree give us shade (树荫), oxygen (氧气) and natural beauty, it is also a great place for a tree house, or a place for us to read a book, listen to music or drink tea. If the adult tree receives proper care, it may continue to live healthily for over 100 years.
Gradually, trees begin to grow older and older and even die. At this time, they still have their important place in nature. Even though a tree becomes hollow or part of it becomes dead, it can provide a home for small animals.
In many ways, the life of a tree is similar to our own life experience. When looking at the life of a tree, we learn that each period of life brings its own form of joy. Enjoy every minute of it and take care of the trees!
