问题 选择题

下列有关CO2的说法,不正确的是(  )。

A.干冰可用于人工降雨

B.CO2可用作气体燃料

C.“碳酸水”的pH小于7

D.大气层中CO2过多会造成“温室效应”

答案

答案:B

题目分析:干冰是固态的二氧化碳,易升华吸热,可用于人工降雨,A正确;二氧化碳不具有可燃性,不能作气体燃料,B错误;碳酸水溶液显酸性,所以pH小于7,C正确;大气中的二氧化碳排放量增大,会引起“温室效应”,D正确。故选B。

单项选择题 B型题
阅读理解

C

The outstretched(伸出的) hand caught my eyes immediately. I’d fallen on the sidewalk, having tripped on the curb(路边). A hand was there, ready to help me. Then, warm smile and, “ Are you OK?”

I’d fallen on my hands and knees, and I was fine. But I loved seeing that hand reaching toward me. The woman helped me up, made sure I was all right, and we both went our way.

As I remembered this incident during the next few days, it became a symbol of the significance of helping another one. In the grand scheme of things, such help may often seem small, but at the moment it’s needed, it can feel very significant.

One of my most meaningful lessons on how to help others came at the end of a week-long music workshop. At that final gathering, we each had the opportunity to perform for the other participants. A woman who was  much more experienced and accomplished(技艺高超的)than I ---- a piano teacher who attended the workshop in order to learn new teaching techniques- invited me to play the piano with her. I'd actually been quite happy as part of the audience, watching the other students perform. My piano skills were elementary, and my confidence was low.

When she asked, though, it was almost as if she’d taken me by the hand and led me to the piano. As I plunked out a melody(旋律), she played a lovely accompaniment. Hearing that accompaniment to my melody moved me to tears. She was helping my music be beautiful—helping me play my song. But the lasting impact of that experience related to much more. I took away with me the lesson that we are each here to help one another “ play our songs” --- live our lives to the fullest, be the individuals whom we are.

63. What is the main idea of the passage?

A. The significance of helping one another.

B. My experience of playing the piano.

C. The people who helped me out.

D. The incident I remembered on the street.

64. Why did the author just want to be part of the audience?

A. She couldn’t play the piano quite well.

B. There was no time left for her to perform.

C. Nobody invited her to play the piano.

D. She was too shy to perform in public.

65. We can infer from the passage that the melody played by the author was ____.

A. moving  B. lovely  C. so-so  D. beautiful

66. Which of the following statements is NOT true according to the passage?

A. The author appreciated the two women’s help.

B. Small help is also important when it is needed.

C. A piano teacher invited the author to play the piano together.

D. The author was moved to tears because of the beautiful music.