Without ecological balance, there is no real economic benefit.

译文：人生得一知己必须要对知己问心无愧，读书人多读书，一定要学以致用。赏析：做人做事凭着良心方能服众，才不会招致怨愤和祸患。读书的目的就是学以致用，我们不能读死书，死读书，我们要让书中的知识来指导我们的生活。

Spend as much time crafting the subject line of an email as the message itself because the subject line is often the only thing people read.