《2025年节节高大象出版社八年级英语上册仁爱版》

C
Comets are parts of our solar system. Like the planets, they go around the sun.
But comets are not made of solid rock like planets. A comet is a ball of dust, stones, and ice. Many people call comets dirty snowballs.
The “snowball” may be only a few miles across. But when the sun heats the “snowball”, much of it is changed to gases. The gases spread out and form the comet’s “head”, and it may be thousands of miles across.
A comet moves fast in its trip around the sun. But when we see it, the comet does not seem to move. That’s because it is so far away. The moon moves fast, but when you look at it, you can’t see any motion (运动). That’s because the moon is far away.
So comets do not rush across the sky. You can’t see any motion. But if you look night after night, you can see that a comet changes position (位置) among the stars. If you watch the moon night after night, you’ll see that it also changes position.
Each year astronomers (天文学家) discover new comets. Some of them are seen only once. They make one trip around the sun and then go into space. The sun’s gravity (重力,引力) can’t hold them.
Other comets, like Halley’s comet, keep returning. They have been captured by the sun. Halley’s comet’s earliest visit was probably 3,000 years ago. It may keep returning for another 3,000 years.
But every time a comet goes around the sun, the comet loses part of itself. Gases and dust are pulled out of the comet. That’s why Halley’s comet is now dimmer (昏暗的) than it used to be. Next time it visits us, in 2062, it may be even dimmer. Each visit it may get dimmer and dimmer, until it finally disappears (消失).
根据材料内容选择最佳答案。
(D)31. What is the text mostly about?
A. Comets and the sun.
B. Why comets are like snowballs.
C. Who discovered the first comet.
D. Facts about comets.
(C)32. What does the underlined phrase “captured by the sun” mean according to the text?
A. The comets are rushing into the sun.
B. The comets have been brightened by the sun.
C. The comets are stuck in the sun’s gravity.
D. The comets have been burned by the sun’s heat.
(D)33. How does the author help the readers understand what a comet looks like?
A. By telling about a famous one.
B. By explaining how far away it is.
C. By describing how fast it moves.
D. By describing it as a dirty snowball.
(A)34. What is the most likely reason the author wrote the text?
A. To give information about comets.
B. To tell readers about famous comets.
C. To explain the importance of comets.
D. To encourage readers to look for comets.
(C)35. What is the best title for the text?
A. The Sun
B. The Moon
C. Comets
D. The Solar System

答案： 31—35 DCDAC