Questions 19 to 21 are based on the passage you have just heard.
A. Strengthening people's immunity to infection.
Better understanding patients' immune system.
C. Helping improve old people's health conditions.
D. Further reducing old patients' medical expenses.
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Questions 22 to 25 are based on the passage you have just heard.[音频]
A. His students had trouble getting on with each other.
B. A lot of kids stayed at school to do their homework.
C. His students were struggling to follow his lessons.
D. A group of kids were playing chess after school.
Questions 22 to 25 are based on the passage you have just heard.
A. Visit a chess team in Nashville.
B. Join the school's chess team.
C. Participate in a national chess competition.
D. Receive training for a chess competition.
Questions 22 to 25 are based on the passage you have just heard.
A. Most of them come from low-income families.
B. Many have become national chess champions.
C. A couple of them have got involved in crimes.
D. Many became chess coaches after graduation.
Questions 22 to 25 are based on the passage you have just heard.
Actions speak louder than words.
B. Think twice before taking action.
C. Translate their words into action.
D. Take action before it gets too late.
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