40．A．clearest         B．clearer and clearer  C．the clearest

    A

  The police do many things for us．They help keep our things and us safe．They help keep cars moving safely．They take care of people who are hurt．

      The police go around towns to see that everything is all right．They get around towns in many ways．Some of them walk or go by car．In some big cities，some of the police are on foot．

    As they go around towns，the police help people．Sometimes they find lost children and take the children home．If the police saw a fight，they put an end to it right away． Sometimes people will ask the police how to get to a place in towns．

    Some police stand at crossings．They make sure that the cars do not go too fast．

Without the police，our streets would not be safe．Cars might go too fast and hurt people．The police do a  good job．We need them．

39．A．Think           B．Guess                  C．Know

38．A．feel              B．meet                    C．watch

37．A．forget           B．forgot                  C．forgetting

36．A．reach            B．arrive                         C．get

35．A．change         B．make                   C．start

34．A．in                B．from                   C．with

33．A．correctly       B．carefully              C．happily