Have you ever heard the old saying, "Never judge a book by its cover."? This is a good rule to follow when trying to judge the intelligence of others. Some people have minds that shine only in certain situations. A young man with an unusual gift in writing may find himself speechless before a pretty girl when he speaks. He may not be able to find the right words. But don't make the mistake of thinking him stupid. With a pen and paper, he can express himself better than anybody else. Other people may fool you into overestimating  their intelligence by putting up a good front. A student who listens attentively and takes notes in class is bound to   make a favorable impression on his teachers. But when it comes to exams, he may score near the bottom of the class. In a word, you can't judge someone by appearance. The only way to determine a person's intelligence is to get to know him. Then you can see how he reacts to different situations. The more situations you see, the better your judgment is likely to be. So take your time. Don't judge a book by its cover. The writer of this passage wants to tell us not to  _  .
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