"What are they showing here？"Yan Hongsen pointed at an educational film about rockets（1）

angrily

angrily

（angry） and asked." This is the Long March 3!Why do they say that this is the Long March 5？"
It was July 16.The nine-year-old boy was visiting a planetarium （天文館） in Lhasa with his father.While watching the film，he noticed a few（2）

mistakes

mistakes

（mistake） and complained.How did the boy know so well about China's space industry？
    The father explained that his son had been interested in space science for years.It all began with his（3）

first

first

（one） visit to the Jiuquan Satellite Launch Center.One day when the boy was four years old，he（4）

was taken

was taken

（take） to see the launch of a satellite.Watching the rocket lift off into the sky with his own eyes，he felt so（5）

excited

excited

（excite） that he jumped up and down.
    Hongsen has been dreaming of building his own rocket（6）

since

since

jye.ain.The boy has read many books，and visited 22 planetariums and science museums across China.He has also used cardboard（7）

to make

to make

（make） his own rocket models.In order to work out some difficult problems，he（8）

has developed

has developed

（develop） an interest in physics，chemistry and computer science these years.
    Hongsen has two role models：Nan Rendong，（9）

a

a

famous astronomer，and Qian Xuesen，the "Father of Chinese Rocketry."The boy hopes that one day，he can be as great as them.What a big goal!（10）

If

If

he can keep on making great efforts to carry out his dream of building a rocket for China，he might just be able to achieve it.