A language is a signaling system (这里对语言下个一个定义,类似的句型还有: A language refers to / is defined as) which operates with symbolic vocal sounds (语声), and which is used by a group of people for the purpose of communication.

　　Let’s look at this 61 in more detail because it is language, more than anything else, 62 distinguishes man from the rest of the 63 world. (61题this definition指代第一句话的内容; it is language that是强调句. 下面一段第一句other animals 暗示了63题填animal distinguish from 表示对比概念. 大家都知道,对比型文章在阅读,完形和改错中都经常出现,所以必须首先掌握这类文章的一些词汇特征,解题的时候也要注意对比概念. 表示对比概念的词汇手段很多,举几个例子: distinct from / differ from / different from / similar to / dissimilar from / in contrast to / on the contrary / as opposed to / while / whereas / but / however 等等)

　　Other animals, it is true, communicate with one another by 64 of cries: (本句也可以变为It is true that other animals communicate with….., 那为什么要写成本文这样呢.如果能知道，大家对英文的理解为更深刻. 这里以other animals 为主语, 使本句话与上一段最后一句衔接更紧密, 因为animals是上句中出现过的概念. 举个作文的例子,很多同学写作文的时候句子之间缺乏coherence, 比如: He got off the plane. Reporters surrounded him. 这两句话虽然没错,但是最好改为:He got off the plane. He was surrounded by reporters 或He got off the plane and was surrounded by reporters)for example, many birds utter 65 calls at the approach of danger; (65题warning和danger相关) monkeys utter 66 cries, such as expressions of anger, fear and pleasure. 67 these various (various 暗示了66题答案) means of communication differ in important ways 68 human language. (67，68题都涉及到对比概念) For instance, animals’ cries do not 69 thoughts and feelings clearly. (69题除了用express以外,也可以用convey) This means, basically, that they lack structure. They lack the kind of structure that 70 us to divide a human utterance into 71 .

　　We can change an utterance by 72 one word in it with 73 : a good illustration of this (举例好句型) is a soldier who can say, e.g., “tanks approaching from the north”, 74 who can change one word and say “aircraft approaching from the north” or “tanks approaching from the west”; but a bird has a single alarm cry, 75 means “danger!” (73题很重要，大家看看replace 的核心意思是不是change, by这个词表示方法,通过什么来改变,四个选项只有replace与 change相关)

　　This is why the number of 76 that an animal can make is very limited: the great tit (山雀) is a case 77 point; (举例好句型) it has about twenty different calls, 78 in human language the number of possible utterances is 79 . It also explains why animal cries are very 80 in meaning. (78题涉及到对比概念，而这篇文章中的主要概念对比，就是强调人与其它动物的对比，这一点大家好好体会。另外， 80题general 这个词的对比词是specific， 尽管文章中没有出现。人的语言可以表达具体特定的意思，而动物发出了声音只能表达笼统的意思。)

　　完形填空的每个空格都受到文章中已经知道的信息点的控制，句子中，前后句子中，或者整个语篇中的信息点的控制。同学们在复习完形的时候，要注意几点，指代，句型，搭配， 对比，词汇相关性。这些我在这篇文章中都举了一些例子说明。

　　本文选项：(黑体为答案)
　　61. A) classification B) definition C)function D)perception 
　　62. A) that B) it C)as D)what 
　　63. A)native B) human C) physical D) animal 
　　64. A) ways B) means C) methods D) approaches 
　　65. A) mating B) exciting C) warning D) boring 
　　66. A) identical B) similar C) different D) unfamiliar 
　　67. A) But B)Therefore C) Afterwards D) Furthermore 
　　68. A) about B) with C) from D) in 
　　69. A) infer B) explain C) interpret D) express 
　　70.A) encourages B) enables C) enforces D) ensures

　　71. A) speeches B) sounds C) words D)voices 
　　72.A) replacing B) spelling C) pronouncing D)saying 
　　73. A)ours B) theirs C) another D) others 
　　74. A)so B) and C) but D)or 
　　75. A)this B)that C)which D)it 
　　76. A)signs B)gestures C)signals D)marks 
　　77. A)in B)at C) of D)for 
　　78. A) whereas B) since C) anyhow D)somehow 
　　79. A) boundless B) changeable C) limitless D) ceaseless 
　　80. A) ordinary B) alike C) common D) general