综合填空。 用方框中所给词的适当形式填空，使短文正确、通顺。每词限用一次。 go  grow  sell  protect  improve  another  animal  please  clean  lucky Have you ever noticed how cool it is to be under trees? Besides the 1 they give, trees can make our life better in other ways, too. Because trees need CO2 when they 2 , they can make CO2 less in the air. Also, trees can give off O2. Trees and forests play an important part in helping 3 our environment. They can stop the soil from being washed away or blown away. They can make water better. And they can make the air 4 . At the same time, forests are the home of many 5 . However, forests in our country and all ore7 the world are becoming fewer and fewer. People cut down trees to make paper or 6 them for money and do other things. For example, between 50 and 100 acres (英 亩) of rainforests are destroyed every minute, if this 7 on, there will be no rainforests left in one hundred years. 8 , many countries come to know the importance of forests. They ask their people to 9 the forests and not to cut down trees too often. If people cut down one tree, they should plant 10 tree or more trees. How about you? Do you want to plant trees for your future? Are you ready? Let's go!