问题 选择题

一物体从某一高度自由落下,落在直立于地面的轻弹簧上,如图所示,在A点,物体开始与弹簧接触,到B点时,物体速度为零,然后被弹回。下列说法中正确的是

A.物体从A下降到B的过程中,速率不断变小

B.物体在B处时,其加速度大于重力加速度

C.物体从B下降到A的过程中,物体的机械能守恒

D.物体从A下降到B的过程中,物体的加速度不断增大

答案

答案:B

阅读理解

阅读理解

     Students will need to use all of their skills in order to understand the reading selections in Reader's

Choice.

     _1_ These selections provide practice on employing different reading skills to get the message of the

writer. They also give students practice in four basic reading skills:skimming, scanning, reading for

thorough comprehension, and critical reading.

     Skimming involves reading quickly through a text to get an overall idea of its contents. This kind of

rapid reading is suitable when you are trying to decide if careful reading is desirable or  __2__

     Like skimming, scanning is also quick reading. However, in this case the search is more concentrated.

__3__  When you read to find a particular date or number, you are scanning.

     Reading for thorough comprehension is carefully reading in order to understand the total  meaning of

the passage. At this level of comprehension the reader is able to summarize the author's ideas   _4_.

     Critical reading demands that a reader makes judgments about what he or she reads. This kind of

reading requires posting and answering questions such as "_5_", "Do I share the author's point of view?"

and "Am I convinced by the author's arguments and evidence?

A. Does my own experience support that of the author?

B. Reader's Choice is one of the most popular magazines in the world.

C. but has not yet made a critical evaluation of those ideas.

D. The book contains many types of selections on a wide variety of topics.

E. To scan is to read quickly in order to find out specific information.

F. Do I know about the author?

G. when there is no time to read something carefully.

单项选择题