题干

在“探究滑块速度随时间变化的规律”实验中,某小组同学在一端装有定滑轮的长木板的中段粘上均匀的薄砂纸,砂面朝上,还选用了质量为100g的长方体木块、一把带毫米刻度的直尺、一段较长的棉绳、一盒钩码(单个质量为50g)、电磁打点计时器、纸带、复写纸和导线若干,实验装置如图甲所示,实验时在小车上加载四个钩码,在棉绳的右端悬挂三个钩码,接通电源,释放小车,成功打出了一条纸带,纸带的局部如图乙,大部分点的时刻和速度的对应关系已经描绘在图丙里.

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                        The Power of -atlon(决心)

    The little country schoolhouse was heated by an old mal stove(火炉).A little boy had the job of coming to school early each day to start the1and warm the room before his teacher and his classmates got there

    One morning they 2to find the schoolhouse burning. They dragged(拖)the little boy out of the building more dead than alive. Then he was 3taken to a nearby county hospital.

    The doctor told the boy's mother that4 the lower part of his body was seriously burnt, he couldn't use his legs anymore. However, the5boy made up his mind that he would walk. Unluckily his thin legs6hung there, all but lifeless.

    Finally he returned home from the7.Every day his mother would press his little legs, but there was no feeling, no control,8.Yet his determination that he would walk was as 9as ever.

    When he wasn't in bed, he would sit in a wheelchair. One sunny day his mother wheeled him out into the yard to get some fresh air. This day, instead of sitting there, he 10himself from the chair and pulled himself across the grass,dragging his11behind him.

    He worked his way to the white fence(栅栏)around the yard. With great effort, he raised himself up on the fence. Then, he began dragging himself along the fence,12that he would walk. He started to do this every day. There was nothing he 13more than to develop life in those legs.

    In the end,through his determination he did14.He began to walk to school,then to run to school,to run15the joy of running. Later in college he made the running team.

      Still later in Madison Square Garden this determined young man, Dr. Glenn Cunningham, ran the world's fastest mile!