UASB反应器的优点包括( )。 A．可形成稳定的生物相 B．较大的絮凝体具有良好

     Last summer I was a volunteer (志愿者) at a shelter(收容所) for the homeless, a place for homeless
people to sleep at night. I wasn't working that summer and was   1   only two classes in summer school,
so I had some   2   time.    
Three nights a week, I   3   in the kitchen of the shelter along with four other volunteers. We planned
and   4   for 45 people hot meals   5   vegetables, chicken, fish and fruit. The homeless people   6   this
good food because many of them usually didn't eat well.
     I   7   this volunteer work, making   8   with the four volunteers in the kitchen. One was a very nice
elderly(上了年纪的) housewife, one a movie actor, another a young teacher, and the other a college
student,   9   me.
     I talked to a lot of the homeless people at the shelter. Their life stories   10  me with sympathy (同情).
Some of them had  11  with alcohol (酒) or drugs while others only had bad   12 . One woman worked
for almost 30 years for a small company, and   13  she lost her job. She looked for a   14  job, but
couldn't
find one, for she was too  15  . She could do nothing but sell her furniture - sofas, chairs, and tables   16 
she could pay for her food. The woman   17  on job hunting, but she   18  couldn't find one. She had no
money for her   19  and had to sleep in her car. Then she had to sell her car. Alone,   20 , and homeless,
she finally came to the shelter.