题目内容
An 18-yek--old boy from New Jersey,Justin Beckerman,has built his own submarine (潜水艇) ！
He calls it The Nautilus.
Justin spent six months and about $ 2,000 building the submarine from the parts he found in stores or online.
"I spent about one or two weeks designing it," Justin said in an interview. " I spent about two more weeks looking for all the parts."
The submarine uses ballast tanks (压载舱) to stay underwater. A ballast tank is part of a submarine that holds water. It lets in water to help the submarine go down and lets water out to help the submarine go up.
Justin also had to work out how to start the submarine. "The submarine has four battery systems (系统) 一three nain systems and one emergency (紧急情况) system,he said. The submarine's batteries allow it to move underwater for about two hours.
Testing a machine underwater can be dangerous,so Justin's parents keep a close watch on him every time he goes down.
He has also made an emergency plan to keep him safe if something goes wrong. He uses a PA system to communicate when he is underwater.
Justin has been building things since he was young" Justin starts with a dream,and he keeps it until Jie works out how to realize it," said Justin's dad. Justin has built other smaller submarines,but not all have been successful. One of them failed because its materials were not strong enough. But Justin kept trying,and finally built the working submarine he has now.
What advice does Justin have for students?"Keep thinking,creating and dreaming."
71. What's the name of Justin's submarine?
Its name is.
72. How long did Justin work on his submarine?
He worked on it.
73. How many battery systems does the submarine have?
It has battery systems.
74. What does Justin do to keep him safe?
He makes an emergency plan,andwhen he is underwater.
75. What can we learn from Justin?
We can learn that we should.
71. The Nautilus 72. for six months
73. 4/four 74. uses a PA system to communicate
75. keep thinking,creating and dreaming
