阅读下面短文，然后按照要求写一篇150词左右的英语短文．
Volunteering can make you happier and help you live longer，according to a new study．A research paper published on Friday in the journal BMC Public Health says doing good deeds for others improves your health．Researchers from the UK's University of Exeter reviewed 40 papers on the effects of doing voluntary work on our health．They found that volunteers had lower rates of depression（消沉），an increased sense of well-being，and a 22 percent reduction in the chances of dying within the next seven years．Australians lead the way in volunteering，with a 36 per cent of the population lending a hand．
Lead researcher Dr Suzanne Richards said："Our study shows that volunteering is associated with improvements in mental health，but more work is needed to show whether volunteering is actually the cause．"She added："It is still unclear whether biological and cultural factors and social resources that are often associated with better health are also associated with a willingness to volunteer in the first place．"In a study from the University of Michigan，researchers suggested three reasons why volunteering may be beneficial．First，it involves physical activity；second，the social connections we make help to reduce our stress；and third，it gives us a deep sense of happiness．
【写作内容】
用约30个词概括上文的主要内容．
用约120个词谈谈志愿者工作的重要性，内容包括如下要点：
对他人的重要性；对志愿者本人有何益处；我们应该怎样对待志愿者工作．
【写作要求】
作文中可以使用亲身经历或虚构的故事，也可以参照阅读材料的内容，但不得直接引用原文中的句子．
作文中不能出现真实姓名和学校名称．
【评分标准】
概括准确，语言规范，内容合适，篇章连贯．