Give the pupils something to do, not something to learn; and the doing is of such a nature as to demand thinking; learning naturally results.
是因为他们行事合理,行事合理来自于受到的熏染得当。 
生命太珍贵,不能浪费在后悔上。
The pace of change demands agility—both in thought and action.
I'm the kind of person that has to learn the hard way.