短语：和传统语法中的短语定义并不相同，实际运用中频率很高，同位语和介词短语，曾经是心中永远的痛之一，可以理解为插入语，也可以是修饰成分1.名词短语：在写作中，多用名词短语而非单个名词做主语或宾语。
例如，The well-dressed young man named shawn.2.同位语短语:跟在一个名词或者代词后面补充说明的成分。
分为限定性和不限定性，这里的限定的定义也适合所谓的定语从句。
非限定性同位语用2个逗号将其和句子隔开，例如，shawn,a well-known teacher,was unemployed.shawn为人名，认识我的人一看就知道，已经非常具体了，因此后面的同位语并不是起到限定和区别的作用，除非天下有千千万万个shawn......限定性同位语不用逗号隔开，例如，A well-known teacher shawn was unemployed.出名的老师多了去了，加上一个shawn就限定这一个老师不是其他的著名的老师。
检验一个同位语是不是限定性可以将其去掉，看对前面的名词是否有影响。
3.动词短语系动词表语：一个名词短语，回指主语。
shawn becomes a well-known teacher.谓语形容词：一个描述性形容词，回指主语。
shawn is handsome.行为动词零补语：一个不及物动词。
shawn smiled.直接宾语：一个名词短语做宾语。
shawn loves the students.双重宾语：一个间接宾语和一个直接宾语。
shawn brings the students a present.辨别间接和直接宾语：间接宾语往往可以在前面加上“for或者to”。
例如，shawn brings a present for the students.宾语和宾补：两个名词短语，都指同一个人或事。
例如，shawn considered edison the man.（edison=the man）双重宾语与动词有关，是动词的内容；宾补结构只涉及两个名词短语宾语和形容词宾补：形容词要回指宾语。
例如，shawn believed edison capable.4.介词短语1）用作形容词的介词短语：The students in the neworiental school admired shawn.名词短语一般是这样的顺序，形容词+名词+介词短语，例如，The brilliant students from shawn's class are always happy.作为形容词的介词短语作为主语的一个问题就是主谓一致：A group of shawn's students are good at Chinese as well.这是经常性错误，这里的be动词应该用is2）用作副词的介词短语修饰动词：如果介词短语能够像副词一样，转移到句首，句子依旧正确，那么该介词短语就是修饰动词的介词短语。
例如：The students shake shawn's hand after class.也作：After class,the students shake shawn's hand.因此，after class是修饰动词shake，说明什么时候shake修饰表语形容词：Shawn is unhappy with the current situation.很明显，不能是修饰名词，也不可能修饰动词，因为介词短语的位置不能转移。
修饰副词：The prince and princess lived happily in the castle.in the castle修饰副词happily非谓语动词1、动名词短语注意：1.动名词短语永远是单数2.阅读中遇见动名词短语可以用it代替，提高阅读的效率。
3.写作中运用动名词短语可以变换句型，使句子简短。
4.如何区别表语和现在进行时：现在进行时是可以变成其他时态的，而充当表语的动名词短语却不行，动名词短语可以用it代替并且句子依旧成立。
His main activity is watching daytime TV.His main activity watched daytime TV.He is watching daytime TV.He watched daytime TV.2、分词短语注意：1.现在分词表主动，过去分词表被动，一个boring的老师让学生烦，一个被学生烦恼的老师。
2.名词不要单独放，有三个选择可以修饰：形容词，形容性从句，分词短语。
不要滥用从句，分词短语使句子简洁。
3.用分词短语修饰名词然后做主语时，谓语单复数由名词决定，不要因为修饰成分而忘记了。
The reporters covering the news/The man wearing the silly shirtThe houses located on the beach4.用一用经常在阅读中出现的非限定性分词短语，显出长短句结合以及变化。
Shawn,muttering under his breath,returned to work.Shawn,upset by Yu,vowed revenge.5.阅读中的指示题经常会遇到，影响阅读效率之一的问题：非限定性分词短语可以从他修饰的名词移开，悬垂分词。
Muttering under his breath,Shawn returned to work.Upset by Yu,Shawn vowed revenge.当分词短语实际上没有修饰主语时，产生悬垂分词。
Wrapped in beatiful paper,Shawn gave Yu his Christmas surprise.3、不定式短语⑴注意：1.不定式做主语永远是单数，用不定式做主语可以达到变换句型，强调目的的作用。
⑵用作形容词的不定式短语The need to sleep was nearly overwhelming.We marked the items to be put on sale.Here is a list of drags for women to aviod during the pregnancy.注意：用作形容词的不定式短语可用代词替换来检验。
⑶用作副词的不定式短语I stayed up all night to finish my book.They sold the bonds to invest in stock market.We finally moved into a hotel for the kids to get some sleep.注意：1.用作副词的不定式短语一般用来回答why的问题，可在to前面加上in order来检验。
2.和副词一样，用作副词的不定式短语也可以移到句首，后面用逗号隔开，因此也要注意悬垂的问题。
⑷用于修饰表语形容词的不定式短语We are ready to go.I am anxious to start packing for our trip.They are ready for us to come in for dinner now.注意：与用作副词修饰动词的不定式短语的区别，可以用移位的方法。
快速提高托福写作水平的几个捷径：1、主语的丰富化：不定式、名词性从句、名词+形容词性从句、名词+介词短语、名词+插入语、动名词短语、分词短语、2、以副词性从句开头：时间：Before the movie even started,I had finished my popcorn.When the movie starts,the theater gets really quiet.地点：Where the accident had occurred,we found broken glass.Everywhere she went,the lamb followed mary.原因：Because she has to lock up tonight,Sue needs the key.Since it was getting pretty one-sided,we left the game early.条件：If I were you,I wouldn’t do that.Unless you want to go yourself,Fred will go to the meeting.让步：Although he didn’t want to,Fred went to the meeting.Even though none of us were very hungry,we went to dinner.3、形容性从句修饰名词：要注意关系代词在从句中充当成分I met with the real estate agent who sold us our house.She married a man whom she had met at work.I contacted the person whose car I bumped into.I finally read the book that you told me about.I took the test which is regarded as the most difficult one.4、名词性从句：作为名词用代词it检验What he does for a living is a big mystery.I know that you are right.We were aware of what we needed to do.That is what we wanted.5、复合复杂句：简单句：Shawn is unhappy with NOS.复合句：Shawn is unhappy with NOS,and he wants a raise.复杂句：Shawn wants a raise because he has to work during the vacation.复合复杂句：Shawn is unhappy with NOS,and he wants a raise because he has to work during the vacation.。