Question

【题目】Have you ever wondered?

（1）Why do airplanes take longer to fly west than east?

It can take five hours to go west-east from New York (NY) to London but seven hours to travel east-west from London to NY. The reason for the difference is an atmospheric phenomenon known as the jet(喷射) stream. The jet stream is a very high altitude wind which always blows from the west to the east across the Atlantic. The planes moving at a constant air speed thus go faster in the west-east direction when the air moving with the wind than in the opposite direction.

（2）What would happen if the gravity on Earth was suddenly turned off?

Supposing we could magically turn off gravity. Would buildings and other structures float away? What happened would depend on how strongly the things were attached to the Earth. The Earth is moving at quite a speed moving at over a thousand miles per hour. If you turn something round your head on a string, it goes around in a circle until you let go of the string. Then it flies off in a straight line. “Switching off” gravity would be like letting go of the string. Things not attached to the Earth would fly off in a straight line. People in buildings would suddenly shoot upwards at a great speed until they hit the ceiling. Most things would fly off into space.

【1】What information can we get from the first passage?

A. It is the jet stream that affects how fast airplanes fly.

B. Planes go slower when they are moving with the wind.

C. It takes more time to fly from NY to London than from London to NY.

D. The jet stream always blows from the east to the west across the Atlantic.

【2】The word “shoot” underlined in the 2nd paragraph probably means“________”.

A. send for B. move quickly C. come out D. grow quickly

【3】It can be inferred that without gravity ________.

A. buildings and other structures would float away

B. trees and buildings would not so easily fly off

C. something around your head would not float away

D. everything outside buildings would fly off into space

【4】Where can we most probably read this text?

A. In a research paper. B. In a short story.

C. In a travel magazine. D. In a students’ book.

Answer 1

【答案】

【1】A

【2】B

【3】B

【4】D

【解析】本篇是说明文，介绍了航天飞机从东往西比从西往东飞行花的时间久的原因和地球引力消失后将要发生的事情。

【1】A 细节理解题。根据第一段中“The reason for the difference is an atmospheric phenomenon known as the jet(喷射) stream.”以及上一句可知，影响航天飞机飞行速度的快慢的原因是喷射气流现象。故选A。

【2】B 词义猜测题。根据“Things not attached to the Earth would fly off in a straight line. People in buildings would suddenly shoot upwards at a great speed until they hit the ceiling. Most things would fly off into space.”可知，失去地球引力后，地球表面的大多数事物（没有依附于地球的）和人都将要快速离开地面。故选B项，move quickly意为“快速移动”。

【3】B 推理判断题。根据第二段中“Things not attached to the Earth would fly off in a straight line.”可推断出，失去地球引力后，树木和建筑物这类的依附于地球的事物是不会轻易漂浮，故选B。

【4】D 推理判断题。本文介绍了一些基础的科普知识，很可能选自学生的课本，不可能来自专业性较强的研究论文，趣味性的短篇故事或者旅行杂志。