15．Let me tell you about a young boy who made a model car all on his own．The boy is me，six years ago when I was just 11．The car was small and simple，but in my imagination it was a high-speed racing car，speeding along the race road．
It was during the school summer holidays and workmen were building a new driveway and garage（车库） beside our house．It meant to add something new to our home．When I watched the workman，I came up with an idea---I would build a car to drive into the garage in celebration of it．I told my mother and began with my plans．But I couldn't find the right things for making the car，so I gave up and sadly spent several days doing nothing．My mother noticed that I had stopped working and asked me why．I explained and she suggested that maybe I should change my plan to fit the things I had，rather than give up．
And that's just what I did．I found small pieces of wood in my father's workshop and made my car from anything that was lying around the house．When I found a small engine（发动机） from one of my old model planes，I added that．The power came from a battery（电池） I found in a box．
By the time the garage was finished，so was my car．I called my family together outside the house，started the engine and put the car on the driveway．It was fast，and I had to run to the garage to prevent it from hitting the new door．My family began to cheer and I smiled proudly．Thanks to my mother I learned the value of continuing to do things，especially something difficult．Soon I was making plans for my next project：a robot!
51．The writer wasA when he made the model car．
A．a student
B．a driver
C．a workman
D．an engineer
52．The writerA making the first planned car．
A．gave up
B．felt excited about
C．was very busy
D．spent several days
53．To help the writer，his motherC．
A．explained the plan to him
B．brought him to the workshop
C．gave him some suggestions
D．found him some pieces of wood
54．By the time the car was finished，B．
A．the writer thanked his mother
B．the family was called together
C．the writer put it into the house
D．the family began a new project
55．What did the writer mainly tell us？A
A．Keep on doing things to the end．
B Think hard before doing something．
C．Always ask for help when in trouble．
D．Try the best to find the right things to do．
