A．Trial-producing smaller cars to replace the bigger ones that are used today.
B．Mass-producing some kinds of cars for tomorrow.
C．Trying to make some new style vehicles that would be faster and safer than the ones used today.
D．Designing some cars that would have many advantages over the ones used today.

A．He can’’t find his office key.
B．He has misplaced some exams.
C．He’’s unable to talk.
D．He doesn’’t like his classroom.