This paper is an interpretation of the public library part of State of America's Library Report 2018. The author believes that  emphasizing social responsibility and focus on investigation and evaluation are two major features that help American public libraries act in services and continue to develop. The public libraries in our country should learn from American libraries in emphasizing the awareness of social responsibility and realizing the service by solving social problems. Attention should also paid to accuracy and persistence. Investigation and evaluation of the services are necessary.