《2025年课堂作业武汉出版社八年级英语上册人教版》

阅读理解
Is there anything worse than trying to watch a video or listen to your favourite music and you can't bear the outside noise even with your headphones on? You're listening to your favourite part of the music and suddenly a car drives by or even worse—someone turns their own music up. Or what about when you're on the bus or subway and all you can hear is traffic? Noise-cancelling headphones are the way to solve the problems. They reduce the noise around you by using something called ANC.
ANC stands for Active Noise Cancellation. A sound is a wave that must reach your eardrum(耳膜) for you to hear it, so an ANC system listens to the noise around you. Then a sound wave is sent out from headphones to cancel(消除) the incoming sound wave of the noise. Finally, the sound wave from headphones stops the sound wave of the noise from having any effect. Think of two waves hitting each other until there's nothing left but calm blue sea.
With the improvement of technology, ANC is becoming more and more efficient and flexible, which can be adjusted to meet the needs of headphone users.
Adaptive noise cancellation(自适应降噪) is a clever kind of ANC. It lets you choose how much background noise you can hear by changing the controls. You can also control how much of your own voice you want to hear, so you can hear yourself talking to friends.
1. What does "They" in Paragraph 1 refer to?
A. Favourite parts of the music.
B. Buses to school.
C. The headphones.
D. The noise problems.
(C)
2. Where may you want to use the ANC?
A. In a library.
B. In a hospital.
C. In the noisy street.
D. In a museum.
(C)
3. The correct order of an ANC system cancelling the noise is ______.
a. It sends out a sound wave.
b. It listens to the noise around.
c. Its sound wave makes the sound wave of the noise unable to work.
A. a—b—c
B. b—a—c
C. a—c—b
D. c—b—a
(B)
4. Adaptive noise cancellation lets its user ______.
A. cover the sealed ear cups
B. control the background noise
C. change his/her own voice
D. control what his/her friends say
(B)
5. What's the main idea of the passage?
A. How noise-cancelling works.
B. Why noise-cancelling is used.
C. What should be done to control noise.
D. Where noise-cancelling is used.
(A)

答案： 1.C 2.C 3.B 4.B 5.A