Now many university teachers are troubled by students' cheating on exams. No matter how hard they try to persuade and to prevent it from happening, this phenomenon seems to be on the increase. In the past, only students poor at study would try to cheat, but now those good students are joining this team. What's more, students who are caught seldom regret their behavior; they only complain about their bad luck. This is really hard to understand for teachers and administrators. The website of a university has started an online discussion about why students cheat on exams, and you are expected to write an article of about 400 words to join this discussion. You can decide the title for your article. In the first pact of your writing you should present your thesis statement, and in the second part you should support the thesis statement with appropriate details. In tire last part you should bring what you have written to a natural conclusion or a summary.