问题 单项选择题

下列()与振动状态无关。

A.振幅

B.位移

C.频率

D.相位

答案

参考答案:B

解析:振动三要素即振幅、频率和相位。

多项选择题
完形填空

I am my mother’s third child. When I was born, her doctor gently explained to my mother that my left arm was    41   , below the elbow (肘部). Then he gave her some    42  . “Don’t treat her any    43   from the other girls. Demand more.” And she    44  .

My mother had to work to support our family. There were five girls in our family and we all had to    45  . Once when I was about seven, I came out of the    46  , “Mom, I can’t peel (削皮) potatoes. I only have one hand.”

“You get back to peel those potatoes, and don’t ever use that as a(n)    47   for anything again!”

Of course I could peel potatoes with my good hand while holding them down with my other arm. There was always a    48  , and Mom knew it. “If you try hard  49  ,” she’d say, “You can do anything.”

Once in the second grade, our teacher had each of us race across the monkey bars (高低杠). When it was my turn, I    50   my head. Some kids    51  . I went home crying.

After work the next afternoon, Mom took me to the school play-ground.

“Now, pull up with your right arm,” she advised. She stood by as I practiced, and she    52    me when I made progress.

I’ll never forget the    53   time I was crossing the bars. The kids were standing there with their mouths open.

It was the way with everything. When I    54   I can’t handle (处理) things, I see Mom’s smile again. She had the heart to    55   anything. And she taught me I could, too.   

41. A. missing               B. broken                 C. diseased            D. short

42. A. warning                B. medicine             C. help                 D. advice

43. A. badly                 B. differently         C. well                  D. normally

44. A. did                      B. refused          C. cried               D. was

45. A. find out                B. work out             C. carry out          D. help out

46. A. kitchen              B. bedroom        C. house               D. school

47. A. idea                   B. change               C. excuse               D. tool

48. A. chance               B. way                 C. time                 D. success

49. A. enough              B. too                  C. again               D. often

50. A. hurt                   B. nodded             C. shook               D. turned

51. A. cheered               B. whispered          C. joked               D. laughed

52. A. helped               B. raised               C. praised              D. protected

53. A. first                    B. last                  C. wondered         D. next

54. A. admit                B. fear                 C. find                 D. realize

55. A. face                   B. teach                C. learn                D. solve