Dear human beings , Hi ! I’m 80 years old now , s o I’ve seen much of the world. We’ve lived on Earth with you for t 1 of years. Each day we r 2 oxygen and remove h armful gas so that you have p 3 air , we cool the air so that you don’t have to run your air conditioners all the time , we help prevent the Earth’s soil from being washed away , and above all ( 最重要的是 ) , we give all kinds of fruits , nuts , beans as w 4 as wood to you. We like the world , we like you human beings , and we would do anything for you. But w e are now in d 5 because of you. You are destroying ( 毁坏 ) us quickly . You are b 6 and cutting down millions of us each year , but you’re not planting e 7 . What would you do if all of us died ? Perhaps you would die , too. Without us , you wouldn’t get some of your important medicine , you wouldn’t have enough material for buildings , f 8 , paper products , and your cities would look ugly. Moreover , air pollution and noise pollution would become worse and worse , your life would turn nasty ( 不舒服的 )... The best thing for you to do now is to s 9 destroying us and start protecting the environment , because we are the best pollution f 10 and we are your best friends ! I wish all the best for you , and good luck ! Your friend , An old tree