听下面一段独白,回答第1至3题。 |
1. What is the talk mainly about? |
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A. The history of life on Earth B. Why there is life on Earth. C. How life on Earth began. |
2. What is necessary for life on Earth according to the speaker? |
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A. Water, temperature and rock. B. Water, oxygen and plants. C. Temperature, gas and plants. |
3. Which of the following does the speaker believe? |
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A. Earth is the only planet with life. B. People must protect their planet. C. Mars is too hot to have life. |