Try To Renew Knowledge The world today to grasp knowledge is to master everything . Mental activity almost replaced physical activity . Some people maybe master some knowledge ,however many of them are old-fashioned . I think this important that try to renew knowledge .Otherwise you will behind it’s sociology. How to renew knowledge . I have some suggestion maybe help you . On the one hand , you can take part in some different courses . On the other hand , self-study is relatively speaking more convenient . because you don’t need got out that more effective . In my view , self-study is become a big trend in today’s era . A common saying more skills without pressure . you will learn more about the new knowledge or often renew it’s right .