What did the man do every Sunday

A．the current public school system is too complicated to be understood
B．the public school system has no choice of what to teach
C．it is difficult to decide whether elementary science should be taught in public schools
D．the educators should take care of both ordinary and gifted students

A．was a train in the evening
B．were trains all night
C．was a train every sixty minutes
D．were no train in the evening

A．of
B．for
C．about
D．to