现在分词和过去分词的主要区别在于：现在分词表主动意义；过去分词表被动意义。
现在分词较过去分词形式灵活，除部分能接宾语之外，可有被动形式(being done)和完成式(having done, having been done), 当然being done和having been done也可理解成过去分词变形为进行式 1. 现在分词作定语
现在分词常接在名词之后作定语，经常可与定语从句替换
如：the man sitting behind me, 相当于：the man who is sitting behind me the kids running about in the garden, 相当于： the kids who are running about in the garden
单个的分词作定语可放在被修饰词之前，如：the sleeping baby, a running nose
改错题中若出现名词之后直接接动词，且之间是主谓关系，但不是句子主谓语，此处必定有错，可改为现在分词作定语
例题： (1)
The boiled point of any liquid is determined by the pressure of the surrounding gases. A B C D
答案：A
应改为：boiling.
解释：沸点的英文表达应该是boiling point. 类似的表达如: boiling water(沸水); boiled表示已完成的状态, 如boiled water意为白开水, 即已沸腾过的水
(2)
The slide rule uses sliding scales with marks ---- numbers and their logarithms. (A) representing (B) represented
(C) are represented
(D) they are representing
答案：A 解释：空格前是句子的主谓成分，空格处需要marks的定语，C, D可先排除；B是被动式，无法接宾语numbers; 因此A正确，是现在分词作定语
2. 现在分词作状语
分词还可在句中作状语，可放在句首、句中或句尾。现在分词作状语时，通常都表示主语正在进行的动作/伴随动作或者表示原因。
1．现在分词短语可以作时间状语，相当于when, while, as soon as等所引导的从句 如：Hearing the news, he couldn't help crying.
= When he heard the news, he couldn't help crying.
2．现在分词短语也可以表示原因，代替由since, as等所引导的从句
如：Not knowing what to do about the situation, she turned to him for help.
=Since she didn't know what to do about the situation, she turned to him for help. Being so poor in those days, we couldn't afford to go to school.
=As we were so poor in those days, we couldn't afford to go to school. 3．如果分词表示的动作发生在主句动作之前，那么此时分词就需要用完成形式 如：Having finished the work, she went to the park.
=After she had finished the work, she went to the park.
特别注意：分词状语的逻辑主语和句子的主语要保持一致
如: Seeing from the moutain, the ocean is emrald green.
此句是一个错误的句子, 因为根据分词状语的逻辑主语和句子的主语要保持一致的原则, seeing的逻辑主语也应该是the ocean, 而the ocean是不能自己seeing的, 应改为Seen from the mountain.
例题： (1)
Snow aids farmers by keeping heat in the lower ground levels, thereby ---- from freezing. (A) to save the seeds (B) saving the seeds
(C) which saves the seeds (D) the seeds saved
答案：B
解释：thereby一词习惯上接现在分词作句子的结果状语，只有B符合要求
考点二 过去分词
1. 过去分词作定语
与现在分词类似，过去分词作定语常可和定语从句替换, 通常表示被动的含义. 如：a theory derived from rich experience
= a theory that has been derived from rich experience a gas composed of four chemical elements
= a gas that is composed of four chemical elements
单个分词可放在被修饰词之前，如：distinguished guests, unexpected trouble
改错题中常考现在分词和过去分词的混用，关键看被修饰词和分词代表的动作是主动还是被动关系。 例如: boiling water (沸腾的水，表示正在沸腾)； boiled water(开水， 表示已经烧开)
2. 同源现在分词和过去分词做定语的区别
有时一个动词词尾分别加上-ing和-ed就构成了一组同源现在分词和过去分词, 这样的例子在英语里很多, 如: interesting/interested, exciting/excited, disappointing/disappointed等, 这些由动词变化而来的分词已经被人们视为形容词了. 但是, 同源现在分词和过去分词做定语时有什么区别呢?
现在分词通常表示某个事物的特性, 通常用来修饰某事或某物, 含有“使人(令人)感到?”的意思, 如: an interesting novel, a confusing question等;
过去分词通常表示人的感受或状态, 意思是“?的?”, 如: a worried look (焦虑的神情) 试比较: an interesting boy (一个有趣的男孩 - 让人觉得很有趣) an interested boy (一个产生了兴趣的男孩
同样, 当同源现在分词和过去分词做表语时, 在意思上也存在同样的区别, 如: The results are very disappointing. (结果很让人失望)
We are very disappointed at the results. (我们对这样的结果很失望)
例题： (1)
The University of Georgia, ----in 1785, was the first state supported university in the United States.
(A) chartered
(B) was chartered (C) it was chartered (D) to be chartered
答案：A
解释：本句主谓结构完整, 缺少的是主语的修饰成分, A构成过去分词短语作定语；B C 的动词结构与原句谓语冲突; D 不定式一般表示即将发生的动作, 与in 1785不符
(2)
A patent gives inventors exclusive rights to their inventions for a fix period of time. A B C D
答案：C
应改为：fixed
解释：fix是动词，不能修饰名词period, 依句意改为分词fixed, “一段固定时间”
(3)
Closed plane figures like the square or the equilateral triangle can be grouped into a class ----polygons. (A) called (B) to call (C) is called (D) call as
答案：A
解释：此句主谓完整, 句中又无连词, 需填的只可能是非谓语成分, A 是过去分词短语作定语, 等效于which is called, 符合题意. C D 属谓语结构, 与原句谓语冲突; B 不定式表用途或目的, 意思不通 3. 过去分词作状语
过去分词也可放在句首、句中、句尾作句子的状语，常表示事件发生的背景或原因， 如：Seen from far away, the islands look like a chain of pearls in the midst of the lake. De
feated in the final, the team gathered to analyze its technical disadvantages.
特别注意：分词状语的逻辑主语和句子的主语要保持一致. 选择题中, 经常要求考生在分词状语部分填入合适的过去分词或现在分词. 到底选择哪种分词, 考生可以采取这样的作题方法: 首先根据“分词状语的逻辑主语和句子的主语要保持一致”的原则确定状语部分的主语, 再判断这个主语和分词是什么关系, 若是主动关系则应该用现在分词, 若是被动关系则要用过去分词.
例题： (1)
---- in 1635, the Boston Latin School is the oldest public school in the United States. (A) Founded (B) Founding (C) To found
(D) Having founded
答案：A
解释：分词部分的逻辑主语也应当是the Boston Latin School, 它和found之间是被动关系, 所以空格处应填入过去分词
(2)
Almost destroy by fire in 1814, the White House was rebuilt and enlarged over A B C the next three year. D 答案：A
应改为：Almost destroyed
解释：by是被动式的标志词, 动词destroy应用过去分词destroyed, 这样既表被动又构成句子的状语
考点三 独立主格结构
独立主格结构是介于分词和主谓句之间的非谓语形式，对于分词来讲其逻辑主语必须和句子的主语保持一致，而独立主格则在很大程度上克服了这一局限性 1、主要特征
(1) 独立主格是含有主语的分词结构，分词与主语间是主谓关系， 基本形式为：主语+现在分词或过去分词 如：his heart bleeding the baby crying
the project completed
The school being over, the street was full of the students.
= When the school was over, the street was full of the students. (2)切记独立主格不等同于主谓结构， 比较：my mind wandering (独立主格)； My mind was wandering (主谓结构)
(3)独立主格的主语和句子主语不一致
如：(With) His mouth filled with water, he couldn't utter a word. (独立主格) 对于分词来讲其逻辑主语必须和句子的主语保持一致:
Filling his mouth with water, he couldn't utter a word.
2. 在句子中的作用
独立主格结构通常在句中表示时间、条件，原因、伴随状态等
如：The film being over, we had a stroll on the nearby street. (时间) Weather permitting, I will go fishing with my family. (条件) Time pressing, they had to work overtime. (原因)
The leaves rustling in the breeze, I roamed on the country road. (伴随)
例题： (1)
----modern offices becoming more mechanized, designers are attempting to personalize them with warmer, less severe interiors. (A) If (B) But (C) With (D)Once
答案：C
解释：句中主干完整, 主语是designers, 谓语是are attempting, 之后是不定式构成的宾语. 空白后 becoming 采取分词形式, modern offices是becoming的逻辑主语, 因此可确定需填入的词会与原句构成独立主格结构, 而不是从句, A B D可一次性排除, 其实此句除去空白处, 已是完整的句子, 类似句子如: The man entered the room, his hair flying in the air.
注意: 表示伴随状态的独立主格结构通常可以由with引导, 如本例题.
第三节 动名词
动名词是动词的特殊形式，拼写类似现在分词，用法类似名词，具有与二者均不同的特点：动名词可作动词或介词宾语（分词不行）之后可以再接宾语（名词不行），它兼备了动词和名词的功能，故称作动名词 考点一 动名词作宾语
1． 许多动词不能接不定式作宾语，同时又需要动宾结构作宾语，此时动名词便可大显身手了，如：enjoy singing（喜欢唱歌）,
avoid looking me in the eye miss crashing into the tree
Fancy meeting you here! (想不到在这里见到你了) 常接动名词doing做宾语的动词有：
enjoy, mind, delay, avoid, consider, deny, miss, escape, fancy, suggest, insist等 另外, 在一些固定用法当中, 也需要用动名词做宾语, 如:
can't help doing, it's no use doing, it's worth doing, be busy doing, feel like doing等. 2. 有的动词既可以用动名词作宾语，也可以用不定式，两者意思区别不大, 如: like, begin, start, love, learn等,
如: She began playing piano when she was five. She began to play piano when she was five.
但是对于remember, forget, try等动词来说，接不定式和接动名词意义不同, 如:
How many people remember listening to the radio broadcast, \(还有多少人记得听过无线广播-- The War of the Worlds) (表示已经听过了) I remember to listen to the radio broadcast, \(我想起来要听广播-- The War of the Worlds) (表示还没有听过)
We must try to work this problem out. (我们必须尽力把这道题做出来)（表示努力，设法） We can try doing it. (我们可以试着做它) （表示尝试） 动名词作介词宾语的情况更加普遍，详见第四章介词-介宾短语
例题： (1)
A mortgage enables a person to buy property without paying for it outright; thus more A B C people are able to enjoy to own a house. D
答案：D
应改为：owning
解释：enjoy doing是固定用法，必须用动名词作enjoy的宾语
考点二 动名词作主语、定语或表语
和名词相仿，动名词可作句子的主语、表语或名词的定语 如：Meeting you is my pleasure. His job is driving a bus.
The opening ceremony will begin in five minutes.
在简单句中, 只能有一个主语和一个谓语, 考试时经常会出现在一个简单句中主语部分不全或干脆没有主语部分, 需要考生将句子补全, 这时要注意的是主语部分只能是名词短语, 动名词短语或不定式短语, 而不能是动词短语或句子, 如: 例题： (1)
---- by transferring the blame to others is often called scapegoating. (A) Eliminate problems
(B) The eliminated problems (C) Eliminating problems
(D) Problems are eliminated
答案：C
解释：此句只是主语部分不完整，可排除A,D; B与句意不符，只有C动名词词组合适，与scapegoating相呼应。注意by后面的短语表示一种方式、手段，而不是被动式的施动者 (2)
---- raw materials into useful products is called manufacturing. (A)Transform
(B) Transforming
(C) Being transformed (D) When transforming
答案：B
解释：此句is之前是句子的主语，之后是谓语，空格处需要一个能接宾语raw materials的名词性结构，这正是动名词所具备的特点，因此答案非B莫属