"Am I my brother's keeper?" The question comes from the Bible . In the Bible, Cain kills his brother Abel. When God asks Cain where Abel is, he replies, "I don't know. Am I my brother's keeper?" by which he means, "Am I responsible   for my brother--his safety and health?" The answer, of course, is "Yes, you are." This sense of responsibility for others is basic to all good societies. And also it is basic to what we call "civil  society". China is now working on building a civil society and the high schools in Shanghai want students to take part in _ through volunteering. They are supposed to do sixty class hours of volunteer work before graduation. This is something new in China, but it is not new in other countries. In the Canadian province of Ontario, high school students are required to do forty hours of volunteering. In some American states, the volunteering requirement is one hundred hours. These students spend about an hour a week during the school year and summer vacations, helping the poor, the sick and the old. They also teach young children to read and help to clean up the environment. And studies have shown that this volunteering experience influences students a lot after graduation. Some of you may be thinking, "Gee, sixty class hours is a lot. How can I find the time?" In fact, if you finish it in three years, you only need to do the work about three class hours a month. And the time is well spent if it helps you realize that "being your brother's keeper" makes you a better person and makes society a better place for everyone. The main purpose of the writing is to  _  .
tell students where to do volunteer work give advice on how to be a good volunteer encourage students to do more volunteer work introduce volunteer work in different countries