所谓垂悬结构(The Dangling Construction)就是一个句子成分，如分词短语，不定式动词短语等，找不到被修饰的主语或被修饰的对象不合逻辑。垂悬结构是种错误的句法，应该避免。
下面是三种常见的垂悬结构及其改正方法：
⒈垂悬分词或分词短语，如：
①Climbing up the hill, several boars were seen.
这句子里的现在分词短语(present participial phrase)修饰主语“several boars”是错的;改正方法有二：
(a)确定是逻辑主语，使句子变成“Climbing up the hill, the explorers saw several boars.”
(b)把现在分词短语扩大为副词分句(也称状语从句)：“When the explorers climbed up the hill, they saw several boars/ several boars were seen.”
⒉垂悬副词短语，如：
After putting a shrimp on the hook, the fish began to bite.
这句的副词短语(adverb phrase)和主语“the fish”有什么逻辑关系呢?真正的逻辑主语应该是“the fisherman”或“the angler”才对。改正方法：
(a) After putting a shrimp on the hook, the fisherman found that the fish began to bite.
(b) After the fisherman had put a shrimp on the hook, the fish began to bite.
⒊垂悬不定式动词短语，如：
To write well, a lot of practice is needed.
To be a loyal employee, a sense of belonging is a must.
这两个句子的不定式动词短语(infinitive phrases)并不能修饰“practice”和“a sense of belonging”，真正的主语必须是“人”，如：
(a) To write well, one needs a lot of practice/a person has to practise a lot.
(b) To be a loyal employee, he or she must have a sense of belonging.
上述三类垂悬结构中，第一类发生的频率，必须注意。但是在下列三种情况下，分词短语是对的，它们并非垂悬结构：
第一，独立结构(The Absolute Construction，见3月7日《中英合谈》)中的分词短语有自己的主语，所以不是垂悬结构。例如：
Such being the case, we can go home now./……it is not wrong to call it a day.
第二，当分词含有介词或连词性质时，它不需要逻辑主语，所以没有垂悬问题存在。例如：
Owing to a lack of funds, the project has to be discontinued.
Provided that there is sufficient time, everyone can do the job better.
第三，当分词短语是用来表示说话者的'态度或意见时，也不需要逻辑主语，因此也不存在着垂悬问题。例如：
Judging from his facial look, the news must have been terrible.
Taken as a whole, there is nothing wrong with the logic behind that idea.
一、冠词a/an
1. a university
2. a useful book
3. a one-hour documentary
4. an honest boy
5. an NBA player
6. a European country
a big success / surprise / rain / mess
great progress! What terrible weather!/What great courage!
二、数词
hundred students; hundreds of student
2.常考序数词
nine-ninth;twelve-twelfth;forty-fortieth;
ninety-ninetieth
3.在某人四十多岁时in one’s forties
我父亲40岁的生日my father’s fortieth birthday
4.分数
three fourths=three quarters(四分之三)
three fourths of the students are.....
three fourths of the water is
5.年代in the 1990s(20世纪90年代) in 1990(在1990年)
三、词性变化
1.形容词和副词
wise-wisely polite-politely safe-safely simple-simply terrible-terribly
noise-noisy-noisily true-truly
以ly结尾的形容词friendly友好的lovely可爱的lively生动的，活泼的
2.动词和名词
invite-invitation(邀请)
invent-invention(发明物)-inventor(发明家)
introduce-introduction(介绍，引言)
direct-director(导演)
四、such/that
修饰可数名词：such+a/an+adj+n=so + adj+ a+n(such a nice pen=so nice a pen)
修饰不可数名词：只用such(such clean water)
So+两少两多many，much，few，little(少)如果little(小)则+such.
常考so little education(少)
such little sheep/children(小)
五、否定倒装
结构：
1. neither + do / does / did / will / have / has+主语
2. neither +情态动词+主语
3. neither + be(am，is，are)+主语
六、从属连词
1. until，常考l结构，主句中经常不直接出现not这个否定词，而是会出现none，nobody，nothing，little，few，hardly等这些否定词
When--not until how long--until how soon--not until
2. since
(a)既然，由于(表原因)，解题通过翻译
(b)自从...以来，解题关注完成时态
3. though/although的考查，注意不能和but连用。
4. while/when的考查：两长while，一长一短，长前通常while，短前when。
解题方法：划出句中的动词，辨析长短(进行为长，过去为短)
5. if/unless时态：主将从现
6. as soon as一....就....
七、并列连词
1. ...
2. ...
3.
4. not also...
注意：
1. ...引导主语，谓语动词只能是复数
2.后三个连接主语，谓语动词就近原则
3.如果题目的意思是两者都能...，那就得抓住谓语动词来判定到底是...还是not only... but also。(通读情景来解答)
八、定语从句
1.指人：who/that/whom
2.指物：which/that
注意：
1.先行词后出现后置定语，不要把后置定语当成是先行词。
2.定语从句也是一个句子，做题结束后可以把关系代词替换成先行词，还原成句子进行检验。
九、宾语从句
解题抓住三要素：引导词，时态，语序，可以抓住任何一个要素作为突破口，排除一些干扰选项后解答。
注意：
1. what's the matter/what’s wrong with/which is the way to本身是陈述语序，无须改变。
2.出现or not，引导词只能用whether
d表委婉语气时，时态不变
I.重点词汇
Test----exam words----vocabulary
Excited----exciting amazing----surprising
sometimes----sometime----some times----some time
for example----such as----like begin with----to begin with
maybe----perhaps----probably affect----influence
problem----question
II.重点词组
…for… king skills
…about… …at all
excited about up
mistakes t of all
begin with r on
afraid of h at
sentences notes
e down sure
with up
up y about
angry with by
other e a problem
rd…as… lain about
ge…into… one’s best
the help of are…to…
k about k off
III.重点句子
1.I learn by studying with a group.
’s too hard to understand the voices.
finds watching movies frustrating because the people speak too quickly.
get excited about something and then end up speaking in Chinese.
don’t you join an English club to practice English.
year my English class was difficult for me.
was easy for me to understand the teacher.
I’m enjoying learning English.
aps we have seen young children playing together.
IV.话题语法
1.谈论学习方法
+v-ing结构做状语
