单项选择题


Passage Two
Questions 29 to 31 are based on the passage you have just heard.

A．Those with frequencies lower than 20 hertz.
B．Those with frequencies about 21,000 hertz.
C．Those with frequencies lower than 20,000 hertz.
D．Those with frequencies higher than 20,000 hertz.
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单项选择题
A．He has had a heart attack because of smoking.B．He has serious lung disease.C．He is coughing because of too much smoking.D．He will go to see a doctor about his coughing.
A．He has had a heart attack because of smoking.
B．He has serious lung disease.
C．He is coughing because of too much smoking.
D．He will go to see a doctor about his coughing.
单项选择题
According to Statistics Canada, most Canadian seniors over 65 ______.
A．move to their children’s place
B．live independently until they die
C．join meaningful privately-sponsored activities
D．become the responsibility of the government
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