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托福考试改错题常考要点及例题分析(上)

2008-10-06来源:
三、谓语动词

(一) 谓语动词的主谓一致

①、主谓分割原则
例1:To the citizens of the United States, the bald eagle,
     A    
   America's national bird, symbolize strength and freedom.
        B      C      D
分析:C错,应改为symbolizes。主语谓语用逗号分割开,主语the bald eagle为单数,谓语动词也应该用单数形式。

②、与后者一致原则
not…but, 强调but后面的名词,
not only…but also

③、与前者一致原则
名词+with/together with/as well as/including+复数名词,谓语用is,
中心词在前面,谓语动词应该与前面的名词保持一致
例:The athlete, together with his coach and
     A      B  C    
  several relatives, are traveling to the Olympic Games.
         D
分析:D错,与谓语动词与the athlete 保持一致,改为is

④、就近原则
or, either…or, neither…nor,
单数名词+or+复数名词+are
如果把句子变为一般疑问句,也就是把be动词提到前面,那么变为is
所以注意一点: 如果是陈述句,靠后面近,用复数
        如果是疑问句,靠前面近,用单数
例:The structure or behavior of many protozoans are
        A      B       
  amazingly complex for single-celled animals.
    C              D
分析:A错,应改为and。从谓语动词是复数形式判断,主语应该为复数,or连接两个名词时动词和后面的名词保持一致,behavior是用单数形式,因此只有改为并列连词and才能使主谓在数上保持一致。

⑤定语从句主语就近原则
There are five apples that are red.
apples是复数,因此从句谓语动词是复数。
例:A rocket burns propellant rapidly and most rockets
      A           
  carry a supply that last just a few seconds.
   B   C    D
分析:D错,应改为lasts。从句的逻辑主语a supply为单数,其谓语动词应为单数形式。

⑥the +形容词主谓一致
The rich are not always happier than the poor.
The rich 表示一类人,应该用复数

⑦、倒装句的主谓一致
改错题倒装句的主谓一致一般考两种情况:
a. there be 句型
there be+名词+名词,那么最近的名词决定其形式
b. between/ among 放在句首+be+名词,名词其实是主语,所以be和名词保持一致
例:There are no known society in which left-handed people predominate.
   A     B      C    D   
分析:there be 句型由最近的名词决定其形式,society当然用单数,A错,there are 改为there is

例:Between the foothills of the Andes and the Pacific
             A     B   
  Ocean are a dry coastal strip averaging about 30
     C        
  miles in width.
     D 
分析:倒装句,are改为is
例:Among the favorite attractions at the National Air and
   A    B       C        
  Space Museum in Washington D.C. are the film
                    D
  presented on the five-story-tall screen.
分析:D错,应改为films , 主语实际上是名词,应该与谓语动词保持一致。

⑧、百分比结构的主谓一致
fifty percent of + 名词
one percent of + 名词
谓语动词的形式和百分比多少没有关系,主要取决于后面的名词,比如:
  one percent of my students + are
  fifty percent of my time is spent on working.
这里要强调两个结构
half of =fifty percent
most of + 可数名词 + are
most of + 不可数名词+ is
例:Nearly half of the ancient meteor craters has been
   A       B         C  
  found in central and eastern Canada.
           D
分析:C错,应改为have been。介词of的宾语为复数名词短语,作主语的中心词half当然表复数,相应的谓语动词应为复数形式。
例:Approximately fifty percent of the package utilized
                 A   B 
  in the United States are for foods and beverages.
              C     D
分析:A错,应改为packages。从谓语动词用复数形式判断出主语是复数名词。注意food用复数表示不同种类的食品,beverage用复数表示不同种类的饮料,故(C)、(D)均没有错。

(二) 谓语动词的时态

①、主要考察时间状语
例 The metal aluminum has been first isolated early in the nineteenth century.
   A        B  C     D
分析:Metal, aluminum同位语,in the nineteenth century为明显表示过去时间的状语, 因此应该用过去时态,把has been改为was

②、For和since的区别
区别一:For 后面使用时间段,since 后面使用时间点
区别二:Since 只能用在现在完成时态,For 最主要用在现在完成时和一般过去时
  I has been a teacher for three years.
  I has been a teacher since 1996.
  I was a teacher for three years. 这种表达可以,for three years表示一段时间,was 表示过去做了三年,现在不是老师了
例: Since 1921 the budget of the United States became
   A      B             
  the primary responsibility of the president.
     C    D
分析:A错,应改 In. since一般要求主句用完成时态,而句中谓语动词为过去式,其时间状语应与之呼应,故改Since为In。
例:Adella Prentiss Hrghes served as manager of
             A  B  C  
  the Cleveland Orchestra since fifteen years.
            D
分析:D错,应改为for。since引导时间状语时,主句谓语动词为一般完成时;主句谓语动词为一般过去时要用介词for;而且一段时间用for, 而不是since。

52. In general, prawns lived in shallow coastal waters or in streams. 
   A       B        C     D
自然现象和客观事实用一般现在时态,live

(三) 谓语的语态
语态主要表示是主动语态还是被动语态。
有四组动词是改错题中常考的:

①、prove
My advice proved to be wrong. 我的建议被证明是错的
尽管是被证明,但习惯上用主动;
例:A majority of the reports received from people claiming
                      A  
  to have seen the legendary Loch Ness Monster have proven to be
    B                  C
  mistakes, misconceptions, or they were being tricked.
                  D
分析:D错,应改为tricks。并列连词 or在此连接名词,如果把D理解为并列句,不仅时态不对,语义也有问题,故将整个句子改为名词。have proven to be是正确的。

②、Locate,Situate
这两个词可以用作主动,表示把…放置在…地方;确定…的位置
  Bats locate obstacles.蝙蝠确定障碍物的位置
这两个词也可以用作被动
  My school was located near the river.
区分locate的主动和被动比较难,但是有一个技巧存在:locate如果用作主动,后面必须跟宾语
例:The center of gravity of the human body ---- behind the hip joint.
   (A)locates
   (B)locating
   (C)to locate
   (D)is located
分析:空格处显然缺谓语动词,故首先排除不能作谓语的B和C。动词locate后面没有宾语,所以用作被动,表示“位于”,所以D为正确选项。

③、表示需要概念的动词
need, want, require等
My watch needed repairing
My watch needed to be repaired.

④、表示人的情感的动词
move, annoy, surprise, please等
He is so moving.  他令人感到感动。
He is greatly moved. 他感到非常感动。
主动和被动技巧总结:
如果句子中有一个“过去分词+by”, 如果断定它是谓语的话,前面必然有be动词
例:The Tennessee Valley Authority has chartered by the
                 A     
  United States Congress in 1933 to construct dams,
                 B
  power structures, and flood-control works along
                    C
  the Tennessee River and its tributary streams.
                D
分析:A错,应改为has been chartered。由信号词by可知前面的谓语动词为被动语态形式。