A father took his children to a wheat field(麦田)and said, "Let's play a game and see who can pick the biggest wheat. But there's a rule: you should only keep going and don't look back. "
The children were confident(自信的) because this game sounded very easy. They walked into the field and looked for the biggest wheat. But there were thousands of wheats and they all looked the same. The children couldn't find the biggest one because they could always find a bigger one. When they came to the end of the field, their hands were still empty. The father said, "There must be a biggest wheat in the field. Maybe when you saw it, you were not sure if it's the biggest one. So, you have nothing in your hands."
This story tells us that we should seize(抓住) the opportunity(机会) when we have it. Don't hesitate (犹豫) because we can't have the same opportunity again.