听力原文： Most of us grow up taking certain things for granted. We tend to assume that experts and religious leaders tell us 'the truth'. We tend to believe that things advertised on television or in newspapers can't be bad for us. However, (l8[C]) encouragement of critical thinking in students is one of the goals of most colleges and universities. Few professors require students to share the professors' own beliefs. In general, professors are more concerned that students learn to question and critically examine the arguments of others, including some of their own beliefs or values. This does not mean that professors insist that you change your beliefs, either. It does mean, however, that professors will usually ask you to support the views you express in class or in your writing. If your premises are shaky, or if your arguments are not logical, professors personally point out the false reasoning in your arguments. Most professors want you to learn to recognize the premises of your arguments, to examine whether you really accept these premises, and to understand whether or not you draw logical conclusions. (19[B])Put it this way: Professors don't tell you what to think they try to teach you how to think. On the other hand, (20[C] if you intend to disagree with your professors in class, you should be prepared to offer a strong argument in support of your ideas, Arguing just for the sake Of arguing usually does not promote a critical examination of ideas. Many professors interpret it as rudeness. Nowadays, most colleges and universities encourage students to ______.