The discovery of an ancient giant panda skull has confirmed its bamboo diet dates back more than 2 million years and may have played a key part in its survival.

A Chinese-US research team reports its results today following studies on a fossil skull found in south China’s Cuangxi Zhuang Autonomous Region in 2001.

The six fossils unearthed in Jinyin Cave are dated between 2.4 and 2 million years ago, according to the report in Proceedings of the National Academy of Sciences, an influential US journal.

Jin Changzhu, of the chinese Academy of Sciences (CAS) and lead author of the paper, said the smaller fossil skull indicates the giant pandas were about a third smaller than today’s pandas.

Researchers knew the panda reached its maximum size about 500,000 years ago, when it peaked ,and then gradually became smaller.

Jin, a paleontologist (古生物學(xué)者) at the Institute of Vertebrate paleontology and Paleoanthropology (古人類學(xué)) attached to the CAS, said the size variation was a basic rule of evolution.

“A species tends to grow bigger when it reaches the peak of its population , but becomes smaller when numbers decline,” he said.

The dental remains of the skull, which is the oldest giant panda skull ever found, are similar to today’s pandas, indicating the type of teeth that could munch (津津有味地嚼)mountains of bamboo. A panda can eat up to 40kg of bamboo per day.

Paleoanthropologist Russell Ciochon, the US co-author at the University of lowa, said the panda’s focus on bamboo could have helped it survive all these years.

“Once an animal begins to rely on a common and stable food source, such as bamboo, it tends to evolve a larger body size,” he said. “As individuals of the evolving species grow bigger, they have a better chance not to be eaten by predators (肉食動物) due to their larger body size.”

1.According to the research of the CAS , there were most pandas in the world .

A. 2 million years ago

B. between 2.4 and 2 million years ago

C. 500,000 years ago

D. Nowadays

2.The underlined word “variation” in para 6 means .

A. fall B. change C. increase D. decrease

3.From the passage, we can learn .

A. pandas began to eat bamboo 2 million years ago

B. a species tends to grow smaller when numbers decline

C. the giant pandas were about a third the size of today’s pandas

D. pandas’ bamboo has played an important role in its development

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There is a story about a man who lost his legs and left arm in an accident. After the accident, only a finger and thumb on his right hand remained.

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He wrote to the prison ministry about sending letters to the prisoners. The prison minister replied, “Writing to the prisoners is acceptable, but your letters will not be answered. ”

Filled with excitement, the man knew he could write his letters. He began sending one-way messages of God’s love, hope, strength, and encouragement. He wrote twice a week, testing his strength and ability to the limit. He poured his heart and soul into his words and shared his experience, sense of humor, optimism, and faith.

It was difficult to write those letters, especially without hope of a reply. One day he received a letter from the prison ministry. It was a short note from the officer who monitored and checked the prison mail.

The letter said, “Please write on the best paper you can afford. Your letters are passed from cell to cell until they literally fall to pieces! ”

No matter what circumstances life may present, we all have unique experiences, abilities, and God-given talents. We can discover ways to reach others who desperately need messages of encouragement and strength.

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書面表達

假如你叫李華,今年暑假即將跨入高三的學(xué)習,壓力很大,想和父母說說心里話,請你用英文在你的博客上用書信形式表達出來。主要內(nèi)容如下:

知心話

感恩

感謝父母的關(guān)心、鼓勵

對父母的期望

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學(xué)習打算

考生自擬(至少寫兩點)

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Dear Mom and Dad,

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____________________________________________________________________

____________________________________________________________________

____________________________________________________________________

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Yours sincerely,

Li Hua

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刪除:把多余的詞用斜線( \ )劃掉。

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Eyes

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Tail

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If asked if space exploration should continue, most Americans would give an immediate response either in favor of continuing or in favor of ending space exploration. A common response would be that space exploration is a waste of money. An average American, uneducated on the subject, might believe that the government is wasting billions of dollars on the research that has no merit. Someone strange to the subject might say that a space shuttle goes up once in a while and that is about all that happens. Research is ongoing and continues when there are no shuttles being launched. This also costs the government money. Does the extreme cost of space exploration make sense?

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A. By offering analyses.

B. By making comparisons.

C. By giving some examples.

D. By presenting research findings.

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3. . Jeff is doing it by sneaking(暗中的) answers to a test. And it's also cheating to break the rules of a game or contest or to pretend something is yours when it isn't. When people cheat, it's not fair to other people. It's tempting(誘惑人的) to cheat because it makes difficult things seem easy, like getting all the right answers on the test. 4. , and it won't help on the next test unless the person cheats again.

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B. Some kids cheat once and feel so bad that they never do it again.

C. Some kids cheat because they're lazy.

D. Kids may also cheat by copying a book report off the Internet and handing it in as it's his or her original work.

E. Cheating can happen in a lot of different ways.

F. But it doesn't solve the problem of not knowing the material(材料).

G. There are plenty of reasons why a kid shouldn't cheat, but some kids have already cheated.

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