Exercise is good for you,but most people really know very little about how to exercise properly.5

问题描述:

Exercise is good for you,but most people really know very little about how to exercise properly.5

后一句的意思应该是,因此你尝试,就可能遇到麻烦.
when是当...时、如果,so是因此、所以,中文意思是貌似都可以,但是还要可考虑英美的习惯吧,毕竟学习人家的语言的.若是有看很多原音的电影之类,就会发现,这样的语气下,so用的很多的.