题目

  A good way to pass an exam is to work hard every day. You may not pass an exam if you only work hard before the exam. If you are getting ready for an English exam, do not only learn grammar rules. Try to read stories in English and speak English whenever you can. Before you start the exam, read the questions carefully. Try to understand the exact (确切的) meaning of each question before you pick up your pen to write. When you finish the exam, read answers once more, correct the mistakes if there are any and make sure that you don’t miss anything out. 根据短文内容，选宇宙是由            组成的。