12．听下面一段材料，回答第18至第20题．
18．What should a monitor do？
A．Help to organize activities for the class．
B．Make a lot of friends．
C．Collect old books and bottles．
19．What did Jenny do to help herself reach her aim？
A．She made a wonderful speech．
B．She held a party at her home．
C．She gave away some money to the poor．
20．Who became the monitor in the end？
A．Jenny B．Bruce． C．Jane．
