单项选择题Questions 14 to 17 are based on the following passage. At the end of the passage, you will be given 20 seconds to answer the questions.
What was Edwin Armstrong’s greatest contribution

A.Developing technology to improve radio reception.
B.Discovering innovative ways to limit radio signals.
C.Using radio to produce sounds clearly.
D.Pioneering in communications industries.


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2.单项选择题Questions 1 to 3 are based on the following conversation. At the end of the conversation, you will be given 15 seconds to answer the questions.
Which of the following statements is TRUE according to the conversation you have heard

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5.单项选择题Questions 4 to 6 are based on the following conversation. At the end of the conversation, you will be given 15 seconds to answer the questions.
What will the father do next

A.Go to his office.
B.Make a little home for the pet.
C.Take his daughter to buy a guinea-pig.
D.Ask his wife’s opinion about buying a pet.

10.单项选择题Questions 11 to 13 are based on the following passage. At the end of the passage, you will be given 15 seconds to answer the questions.
What is the finding of scientists

A.Plants can save water.
B.Photosynthesis is complex.
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