It was the last day of the final exam in a college. Outside the classroom, a group of students were waiting for the last exam. On their faces was confidence. They knew the exam would be easy. The teacher said they could bring any books or notes during the test. Right after they came into the classroom. The teacher handed out the papers. There were only five questions on it. Three hours passed. Then the teacher began to collect the papers. The students no longer looked _ but they looked very nervous. The teacher watched these worried faces, and then asked. "How many of you finished all five questions?" No one answered. "How many of you answered four?" Still no one put up the hand. "Three? Two?" The students moved restlessly in their seats. "One, then? Certainly somebody finished one." But the class kept silent . The teacher said, "That is what I thought. I just want to make you know clearly that you finished four years of study, but there are still many things about the subject you don't know. These questions you could not answer are common  in everyday life." Then, he smiled and said "You will all pass this exam, but it doesn't mean that you learned the subject well. There are still more things for you to learn in your later life." Now we can't remember the name of this teacher clearly, but we can't forget the lesson he taught us. What's the best title for the article?
Some confident students. An easy exam. An interesting teacher. An unforgettable lesson.