7、Nothing is small in the world, and too often the smallest carelessness or mistake can lead to miserable catastrophes. As are shown in the pictures, a train is turned over because a rail spike is loose without being fastened. Also, a severe forest fire breaks out due to a lighted butt thrown without being put out. Still, a great dam is destroyed as a result of a tube fountain in a dam without being found out. Therefore, from the above examples we can learn that any behavior of carelessness or no responsibility or a small fault will result in great damage or disaster to our life.