21.
A. By observing their facial features carefully.
By focusing on a particular body movement.
C. By taking in their facial expressions as a whole.
D. By interpreting different emotions in different ways.
Questions 22 to 25 are based on the passage you have just heard.22.
A. They have to look for food and shelter underground.
B. They take little notice of the changes in temperature.
C. They resort to different means to survive the bitter cold.
D. They have difficulty adapting to the changed environment.
23.
A. They have their weight reduced to the minimum.
B. They consume energy stored before the long sleep.
C. They can maintain their heart beat at the normal rate.
D. They can keep their body temperature warm and stable.
24.
A. By staying in hiding places and eating very little.
By seeking food and shelter in people’s houses.
C. By growing thicker hair to stay warm.
D. By storing enough food beforehand.
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