《2025年新课程学习与检测九年级英语全一册人教版》

B
Energy is the ability to do work. Solar energy comes from the Sun. There is also energy that comes from wind and water.
But do you know that energy can come from people, too? When you pedal a bike, you produce energy. You use your legs to push the pedals. Your energy is transferred (转移) to the bike. That makes the bike move.
Now imagine riding your bike to create enough power to run a computer. Some students at one school did just that! They jumped on bikes connected to generators (发电机) and pedaled in place. Soon they were producing electricity. This energy is needed to run their computers.
Here is how bicycle-powered energy works. When a student pedals the bike, the back wheel spins. The wheel spins the generator. The generator produces electricity. As long as a student pedals the bicycle, electricity moves through the generator. The electricity can be used right away. This energy can also be stored and used later.
People use bicycle-powered energy to run small devices(设备) such as small tele-visions and fans. They often use less than 100 watts per hour. However, it would be a mistake to use pedal power to run a fridge. This large machine often uses more than 700 watts per hour. The electricity for these machines comes from power lines over-head or underground.
Pedal power can be seen in schools, gyms, and homes. What a fun way to provide electricity!
21. How does the writer lead into the topic “bicycle-powered energy” in Paragraph 2?
A. By asking a question.
B. By telling a joke.
C. By using an old saying.
D. By making a survey.
22. What does the underlined word “spins” mean in the text?
A. Falls down suddenly.
B. Breaks up completely.
C. Moves up and down slowly.
D. Turns round and round quickly.
23. What is Paragraph 5 mainly about?
A. The future of new energy.
B. The forms of world’s energy.
C. Using bicycle-powered energy.
D. Producing bicycle-powered energy.
24. What do we know about bicycle-powered energy?
A. It can’t be seen in schools.
B. It comes from wind and water.
C. It can be stored and used later.
D. It’s from power lines overhead.
25. In which unit of a textbook can the text be found?
A. Unit 1 Friends Forever
B. Unit 2 Dream of the Stars
C. Unit 3 The Value of Money
D. Unit 4 The World of Science

答案： 21.A 22.D 23.C 24.C 25.D