四、阅读表达
Do you know something about tree rings (年轮)? Do you know they can tell us what the weather was like, sometimes even hundreds of years ago? Trees can keep a record of Earth's climate for a very long time. In fact, trees can live for hundreds and sometimes even thousands of years.
A tree will grow well in a climate with lots of sunshine and rainfall. And little sunshine or rainfall will limit (限制) the growth of a tree. We can see the change of climate by studying the tree rings. For example, to find out the weather of ten years ago, count the rings of a tree from the outside to the inside. If the tenth ring is far from the eleventh ring, then we're sure that it was sunny and rainy most of that year. If it is near to the eleventh ring, then the climate that year was bad.
Tree rings are important not only for studying the history of weather but also for studying the history of man. Many centuries ago there lived a lot of people at a place in New Mexico. But now you can find only sand there — no trees and no people. What happened?
A scientist studied the rings of dead trees there. He found that the people had to leave because they had cut down all the trees to make fires and buildings. As all the trees had gone, the people there had to move.
1. What is the article about?
It's about .

2. In what kind of climate will the trees grow well?
A tree will grow well in a  .

3. If we see the tenth ring is near to the eleventh ring, what are we sure?
We are sure the climate that year was .

4. Can you find any people at a place in New Mexico now?
.

5. Why did people have to leave the place in New Mexico?
Because they had cut down all the trees to .

五、书面表达
以“My Favourite Animal”为题，写一篇短文。要求：运用本单元所学词汇，介绍你最喜欢的动物的外貌、习性、生活环境等，词数不少于 80。