Eye behavior, involving varieties of eye-contact, can give subtle messages which people pick up in their daily life.Warm looks or cold stares tell more than words can. Meeting or failing to meet another person's eye produce a particular__1__ effect. When two American look searchingly at each other's __2__ eye, emotions are heightened and the relationship becomes closer. However, Americans are careful about where and __3__ when to meet other's eye. In our normal conversation, each eye-contact lasts only a few seconds before one or both individuals look away, because the longer meeting of the eyes is rare, and, after it happens, can generate a special kind of __4__ human-to-human awareness. For instance, by simply using his eyes, a man can make a woman aware of him comfortably or uncomfortably; a long and steady gaze from a policeman or judge intimidates accursed. In the US proper street behavior requires__5__ a nice balance of attention and inattention. You are supposed to look at a passer-by just enough to show that you are being aware __6__ of his presence. If you look too little, you appear haughty; too much, inquisitive. Much eye behavior is such subtle that our __7__ reaction to it is largely instinctive. Besides, the codes of eye behavior vary dramatically from one culture to other. In the __8__ Middle East, it is impolite to look at the other person all the time during a conversation; in England, the polite listener fixes the speaker with an inattentive stare and blinks eyes occasionally__9__ as a sign of interest and attention. In America, eye behavior functions as a kind of conversational traffic signal control the __10__ talking pace and time, and to indicate a change of topic. If you can understand this vital mechanism of interpersonal relations,the basic American idiom is there.