community service

名词 community service:

1. a service that is performed for the benefit of the public or its institutions
   同义词：public service
2. an unpaid service for the benefit of the public that is performed by lawbreakers as part (or all) of their sentence

1. Many retirees volunteer in community service and day care centers.
   许多退休人员在社区服务或育婴中心做义务工作
2. Everyone should invest some time in community service.
   每个人都应该花些时间在社区服务上。