Have you ever heard the old saying 'Never judge a egg by its shell'? This is a good rule to follow when trying to judge the intelligence (智力) of others. Some people have minds that shine only in certain situations. A young man with an great gift in writing may be speechless before a pretty girl. When he speaks, he may not be able to find the right words. But you don't make the mistake of thinking him stupid. With a pen and paper, he can express himself better than anybody. Other people may fool you into overestimating (过高估计) their intelligence by putting up a good front. A student who listens attentively (注意地) and takes notes in class is sure to make a good impression (印象) on his teachers. But when it comes to exams, he may score near the bot- tom of the class. It all boils down to this —you can't judge someone by appearance. The only way to judge a person's intelligence is to know him. Then you can see his reaction (反应) to different situations. The more situations you see, the better your judgement is likely to be. So take your time. Don't judge the egg by its shell. The passage suggests that___________.