"but i was a worrier even then. I used to stew and fret about the mistakes I had made. If I turned in an examination paper, I used to lie awake and chew my fingernails for fear I hadn't passed. Then one morning, our class filed into the science lab, and there was the teacher with a bottle of milk prominently displayed on the edge of the desk. We all sat down staring at the milk, and wondering what it had to do wtih the hygiene course he was teaching. Then, all of the sudden, he the teacher stood up, swept the bottle of milk with a crash into the sink and shouted: 'Dont cry over spilt milk!' He then made us all come to the sink and look at the wreckage. 'Take a good look,' he told us, 'because I want you to remember this lesson the rest of your lives. That milk is gone-you can see it's down the drain; and all the fussing and hair pulling in the world wont bring back a drop of it. With a little thought and prevention, the milk might have been saved. But its too late now-all we can do is write it off, forget it, and go on to the next day."