阅读短文，从方框中选择适当的淘并用其正确形成填空，使短文通顺、意思完整。请将答案写在短文后相应题号的横线上。每空限填一词，每词限用一次。方框中有两个词是多余的。

work  help  time   volunteer  for  when  they  with  I  difficult  glad  walk

    You don’t have to give thousands of dollars to help someone .  Sarah，a girl from Michigan，the USA ,makes a difference just by giving her  66  . Sarah was seriously in  67   she was a baby.  It is  68  for her to move．Sarah has to   69   around with a walker，however，the 11-year- old girl doesn’t give up,  and she uses her experience to help others.
Last summer , Sarah  70  three days a week for seven weeks at the Grand Rapids Comprehensive Therapy  Center. She was one of the youngest   71   for “Therapy and Fun",  a program for children with special needs .Her job was to help than and provide them    72   advice and encouragement.
Sarah says that she’s   73   she can share knowledge with others ,  and that working at the center  taught her a lot,  "I feel my life is getting better because I can help others in    74  way.”she said .Mary, Sarah’s fourth - grade teacher said that Sarah has the help of other students around her ,  but shows than that she’s there to    75   them , too.