根据短文回答 16～22 题。 Friendship Friends play an important part in our lives,and although we may take the fact of friendship for granted,we often don't clearly understand how we make fiends.While we get on well with a number of people,we are usually friends with only a very few—for example,the average among students is about 6 per person Moreover, a great many relationships come under the blanket term＂friendship＂.In all cases,two people like each other and enjoy being together, but beyond that,the degree of intimacy between them and the reasons for their mutual interest vary enormously. Initially, much depends on how people meet.and on favorable first impressions.As we get to know people,we take into account things like age,race,physical attractiveness,economic and social status,and intelligence.Although these factors are not of prime importance,it is more difficult to relate to people when there is a marked difference in age and background. On a more immediate level,we are sensitive to actual behaviors, facial expression,and tone of voice,Friends will stand closer together and will spend more time Looking at each other than mere acquaintances.Smiles and soft voices also express friendliness。and it is because they may transmit the wrong signals that shy people often have difficulty in making friends.A friendly gaze with the wrong facial expression can turn into an aggress we stare,and nervousness may be misread as hostility.People who do not look one In the eye are mistrusted when,in fact。they simply lack confidence. Some relationships thrive on argument and discussion,but it is usual for close friends to have similar ideas and beliefs,to have attitudes and interests in common—the,often talk about' being on the same wavelength'.It generally takes time to reach this point；sometimes people。click' immediately.The more intimately involved people become,the more they rely on one another.People want to do friends favors and hate to let them down.Equally, friends have to learn to make allowances for each other, to put-up with irritating habits,and to tolerate differences of opinion.Imagine going camping with someone you occasionally meet for a drink! In contrast with marriage.there are no friendship ceremonies,no rituals to strengthen the association between two people.But the mutual support and understanding that results from shared experiences and emotions does seem to create a powerful bond,which can overcome differences in background,and break down barriers of age,class or race. 第 16 题 The average student has about six friends.（ ）