It’s a sure sign that summer is over and winter is on the way — leaves that were once deep green turn red, yellow and bright orange. It happens every autumn. But did you ever wonder why?

The leaves start changing color when the nights start getting longer and the temperature starts getting cooler. Some scientists think that as the number of daylight hours shrinks, the leaves stop making chlorophyll which makes plants green. The reason is that the process of making chlorophyll requires sunlight. But according to horticulture (园艺) educator Susan Rose from Colorado State University, it turns out leaves don’t really change color at all. “The fall colors are actually there all along,” she said. “But they are covered by the green chlorophyll. As the chlorophyll stops being produced, the other colors can shine through.”

The kind of color that the leaves are going to change to is determined by the plant’s genetic (基因的) background. In some places, the leaves start changing color in September — before autumn even officially begins. In other places, they don’t change until late October or even November. Some scientists say the leaves have been changing color later than usual in recent years. And they think global warming has something to do with that.

In one study, researchers found that the growing season in the Northern Hemisphere was nearly a week longer, on average, in 2008 than it was in 1982. And a professor from Harvard University found that the leaves, west of Boston, Massachusetts, are changing color about three days later than they used to. However, other scientists disagree with the global warming theory. Susan Rose said the leaves in her part of Colorado are changing “right on schedule.” But the leaves in other parts of that state are running a little late. “The lateness in the mountains may have something to do with the really warm late summer and early fall,” she said. “But I’m afraid that’s just a guess.”

1.According to Susan Rose, _____.

A．the fall colors are always in leaves

B．leaves make chlorophyll all the seasons

C．leaves’ changing color have nothing to with the weather

D．leaves begin changing color because they start making chlorophyll

2.The underlined word “shrinks” in Paragraph 2 could best be replaced by _____.

A．reduces          B．increases          C．lasts              D．appears

3.Scientists guess leaves change color later than usual probably as a result of _____.

A．genetic background                     B．dry weather

C．global warming                         D．low temperature

4.The purpose of the last paragraph is to tell readers _____.

A．why leaves change color at fall

B．leaves change color at different time

C．the effects of the global warming on plants

D．different opinions on the lateness of leaves’ changing color

Dear Editor,

I’m a Senior I student in a middle school. This term, my favorite teacher, Miss Mao, no longer teaches us. I want to see her, but I’m afraid that she no longer likes me and I don’t want to trouble her. I really miss her. What should I do?

                                                                Tian Yan

Dear Tian Yan,

It’s bad luck that you have lost your favorite teacher, But if she is still in your school , nothing can stop you going to see her. When she isn’t busy, ask her if she minds having a quick chat. You can then tell her she was your favorite teacher------ everyone is happy to know that they are liked!

If she has left the school, it will be more difficult to meet her. It will be hard, but remember people always come and go in their lives. We can’t rely on them to be with us all the time.

You may be sad to say goodbye to her, but we can remember and learn from her. Think of her best qualities.

You could also try looking for similar qualities in your other teachers. Study hard and give your new teacher a chance.In time, you might start to see that he or she has different qualities to learn from.

Finally, you can not completely rely on other people to get you through your studies , or even your life.

                                                          Editor

The letters are from________.

   A book      B newspaper   C poster     D advertisement

Which of the following does the editor advise Tuan Yan NOT to do?

  A Find a time to see Miss Mao    B Have a short chat with Miss Mao

  C Tell Miss Mao she likes her     D Keep quiet about the thing

According to the passage, students can make progress in their studies _______.

  A completely by their favorite teachers  B completely by their favorite classmates

  C mainly by their parents             D mainly by themselves

Dear Editor,
I’m a Senior I student in a middle school. This term, my favorite teacher, Miss Mao, no longer teaches us. I want to see her, but I’m afraid that she no longer likes me and I don’t want to trouble her. I really miss her. What should I do?
Tian Yan
Dear Tian Yan,
It’s bad luck that you have lost your favorite teacher, But if she is still in your school , nothing can stop you going to see her. When she isn’t busy, ask her if she minds having a quick chat. You can then tell her she was your favorite teacher------ everyone is happy to know that they are liked!
If she has left the school, it will be more difficult to meet her. It will be hard, but remember people always come and go in their lives. We can’t rely on them to be with us all the time.
You may be sad to say goodbye to her, but we can remember and learn from her. Think of her best qualities.
You could also try looking for similar qualities in your other teachers. Study hard and give your new teacher a chance.In time, you might start to see that he or she has different qualities to learn from.
Finally, you can not completely rely on other people to get you through your studies , or even your life.
Editor
【小题1】The letters are from________.
A book      B newspaper   C poster     D advertisement
【小题2】Which of the following does the editor advise Tuan Yan NOT to do?
A Find a time to see Miss Mao    B Have a short chat with Miss Mao
C Tell Miss Mao she likes her     D Keep quiet about the thing
【小题3】 According to the passage, students can make progress in their studies _______.
A completely by their favorite teachers  B completely by their favorite classmates
C mainly by their parents            D mainly by themselves

Dear Editor,
I’m a Senior I study in a middle school. This term, my favorite teacher, Miss Mao, no longer teaches us. I want to see her, but I’m afraid that she no longer likes me and I don’t want to trouble her. I really miss her. What should I do?
Tian Yan
Dear Tian Yan,
It’s bad luck that you have lost your favorite teacher, But if she is still in your school , nothing can stop you going to see her. When she isn’t busy, ask her if she minds having a quick chat. You can then tell her she was your favorite teacher------ everyone is happy to know that they are liked!
If she has left the school, it will be more difficult to meet her. It will be hard, but remember people always come and go in their lives. We can’t rely on them to be with us all the time.
You may be sad to say goodbye to her, but we can remember and learn from her. Think of her best qualities.
You could also try looking for similar qualities in your other teachers. Study hard and give your new teacher a chance. In time, you might start to see that he or she has different qualities to learn from.
Finally, you can not completely rely on other people to get you through your studies , or even your life.
Editor
【小题1】 The letters are from________.

B
Dear Editor,
I’m a Senior 1 student in a middle school. This term, my favourite teacher, Miss Mao, no longer teaches us. I want to see her, but I’m afraid that she no longer likes me and I don’t want to trouble her. I really miss her. What should I do?
Tian Yan  
Dear Tian Yan,
It’s bad luck that you have lost your favourite teacher. But, if she is still in your school, nothing can stop you going to see her. When she isn’t busy, ask her if she minds having a quick chat. You can then tell her she was your favourite teacher. Everyone is happy to know they are liked!
If she has left the school, it will be more difficult to meet her. It will be hard, but remember people always come and go in our lives. We can’t rely on（依靠） them being with us all the time.
You may be sad to say goodbye to her, but we can remember and learn from her. Think of her best qualities.  
You could also try looking for similar qualities in your other teachers. Study hard and give your new teacher a chance. In time, you might start to see that he or she has different qualities to learn from.
Finally, you can not completely rely on other people getting you through your studies, or even your life.
Editor      
35. Tian Yan ______.
A. is a troublemaker     B. likes Miss Mao very much    
C. is happy these days     D. doesn’t like to tell her secret to anyone
36. Which of the following does the editor advise Tian Yan NOT to do?
A. Find a time to see Miss Mao.     B. Have a short chat with Miss Mao.  
C. Tell Miss Mao she likes her.      D. Keep quiet about the thing.
37. The expression “in time” in this passage means “______”.
A. over a period of time    B. on time        C. at the right time      D. a long time ago
38. According to the passage, students can make progress in their studies ______.
A. completely by their favourite teachers     B. completely by their favourite classmates
C. mainly by their parents                 D. mainly by themselves