题目

下图是某种遗传病的系谱图(该病由一对等位基因控制)，其最可能的遗传方式是 A．X染色体上显性遗传                   B．常染色体上显性遗传 C. X染色体上隐性遗传                   D．常染色体上隐性遗传 答案：B Peter was nine years old. He had to go to school five days a week. It was Monday,and he didn't feel well again. He always felt terrible on Monday mornings,because he didn't like to go to school. It was difficult for him to go back to school on Mondays.  It was seven o'clock,but he still stayed in bed. He wanted to find out an excuse (借口) . A headache? No. He had used the excuse many times. Then he remembered his teeth. One of his teeth was loose (松动的) .Great!He started to groan (呻吟) .  "What's the matter?" his father asked him.  "I have a toothache."  "Open your mouth and let me have a look , ” said his father. "Oh,the tooth is loose. Lie down and have a rest. I'll call the dentist."  Peter was a little nervous (焦虑的) ."Why do you call the dentist?"  "I'll ask him to pull (拔，拉) the tooth out."  "Don't pull it out,please,Dad!I can go to school now. ”With these words,Peter got out of the bed quickly.根据短文内容，选择最佳答案。(   ) 1. How long did Peter have to go to school a week?   A. Six days.   B. Seven days.   C. Five and a half days.   D. Five days.(   ) 2. Why did Peter always feel terrible on Monday mornings?   A. Because he was ill.   B. Because he didn't like to go to school.   C. Because he didn't eat breakfast.   D. Because he slept late.(   ) 3. What excuse did Peter find out at last?   A. A toothache. B. A headache.   C. A cough. D. A fever.(   ) 4. What did Peter's father want to do?   A. He took Peter to a hospital.   B. He helped Peter to pull the tooth out.   C. He called a dentist.(   ) 5. Which of the following is NOT true?   A. Peter always had a headache on Monday mornings.   B. Peter didn't pull the tooth out at last.   C. Peter's father didn't believe that Peter had a toothache.   D. Peter went to school on that Monday morning.