A. Many species remain unknown to scientists. B. Only a few species cause trouble to humans. C. They help farmers keep diseases in check. D. They live in incredibly well-organized colonies.
A. They like to form colonies in electrical units. B. They can survive a long time without water. C. They can cause damage to people's homes. D. They are larger than many other species.
A. Refrain from eating sugary food. B. Destroy their colonies close by. C. Keep doors and windows shut. Deny them access to any food.
A. The function of the human immune system. B. The cause of various auto-immune diseases. C. The change in people's immune system as they get older. D. The viruses that may infect the human immune system.
A. Offer blood samples. B. Help to interview patients. C. Act as research assistants. D. Report their illnesses.
A. Strengthening people's immunity to infection. Better understanding patients' immune system. C. Further reducing old patients' medical expenses. D. Helping improve old people's health conditions.
A group of kids were playing chess after school. B. His students were struggling to follow his lessons. C. A lot of kids stayed at school to do their homework. D. His students had trouble getting on with each other.
A. Join the school's chess team. B. Visit a chess team in Nashville. C. Receive training for a chess competition. D. Participate in a national chess competition.
A. Many have become national chess champions. B. Most of them come from low-income families. C. A couple of them have got involved in crimes. D. Many became chess coaches after graduation.
A. Think twice before taking action. B. Actions speak louder than words. C. Take action before it gets too late. D. Translate their words into action.
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