题目内容：

阅读下面材料，在空白处填人适当的内容(1个单词)或括号内单词的正确形式。

More and more public schools in America make it a rule that students must finish a certain amount of community service 1.they are allowed to graduate from high school. They work on projects like making the environment better or 2. (feed) homeless people.

Many school systems in the United States now ask students 3.(do) some kinds of community service as part of their studies. Students involved in service projects help 4.(they) as well as their communities. They learn about the needs of people and aid 5.(organize).For this reason, holidays 6.(become) the prime period for volunteer work so far. Volunteers get no pay, but experts point out that it is 7. excellent opportunity to learn and practice new skills.

According to the statistics, more than 60% of young Americans have participated8.different kinds of community service, such as cooking for homeless people, or painting old buildings, etc. Some students like to do their volunteer work in 9.(centre) parts of America, but the majority of teens prefer to do it in their hometowns. Tom, a 16-year-old middle school student in California, often10.(do) community service in a local hospital. He works 16 hours every week either receiving calls at the information desk, or helping push patients back to their wards(病房).