2007年成考英语（完型填空）答题技巧（二）

　　Passage 21

　　A language is a signalling system which operates with symbolic vocal sounds， and which is used by a group of people for the purpose of communication.

　　Let us look at this definition __1__ more detail because it is language， more __2__ anything else， that distinguishes man from the vest of the animal world.

　　Other animals communicate __3__ one another by means of cries： for example， many birds utter warning calls at the approach of danger； apes utter different __4__， such as expressions of danger， fear and pleasure. But these various means of communication differ in important ways from human language. For instance， animals' cries are not articulate. This means， basically， that they lack structure. They lack， for example， the kind of structure __5__ by the contrast between vowels and consonants. They also lack the kind of structure that __6__ us to divide a human utterance into words.

　　We can change an utterance __7__ replacing one word in it by another： a good illustration of this is a soldier __8__ can say， e.g. ， “tanks approaching from the north”， or he can change one word and say “aircraft __9__ from the north” or “tanks approaching from the west”； but a bird has a single alarm cry， which __10__ “danger！”

　　文章第一句话，主题句

　　signalling 信号

　　vocal 嗓音的

　　symbolic 象征的

　　communication 交流

　　operate 起作用、发生影响。