参考答案  

一、BCACC  AAADC

二、ADAAC  CA

三、ACC  CDA

四、44.Mark Hill is a traffic police officer.

45.He deals with anyone is the accident who is injured. Then he has to clear the road and gets the traffic moving again.

46.Most accidents happen because people drive too fast-especially when the roads are wet. Sometimes accidents happen because drivers don't follow the rules.

47.Long jump   ng   49.His sister   50. hiking    ng