1．该双写却没有双写的单词（必须双写）

unforgettable,written , inferred, referred ,  occurred, regretting, robbed , permitted, forgetting, wrapping, preferred, begged,  hugged; planned; dropped, winning,   cutting, beginning,  hitting  ，stopping
2．不该双写却双写的单词（括号中为错词）
writing (错误writting) ,    eaten (错误eatten)    suffered (错误sufferred 这个单词不同于refer，因为它的重音在第一个音节上，因此fer属于非重读音节不双写)

3．词性变化时必须去掉字母e的单词  unbelievable---unbelievable, value--valuable, argue-argument, true---truly, terrible--terribly, simple---simply possible--possibly,   probable---probably, gentle---gently 

4．词性变化时不能去掉字母e的单词（去e 的根本目的是不让新单词产生太大的发音变形，以下不去e，也是为了不产生发音变形）

changeable,    chargeable,   moveable

5．变化非常特别的单词(英语变化归根结底是根据发音）    panic-panicked-panicking，traffic-trafficking, stomach-(pl.) stomachs 

6.常考的动词变名词

pronounce--- pronunciation explain----explanation                          prepare---preparation Combine---combination recommend---recommendation                                                        

laugh→laughter    consider → consideration,  recognize →recognition,    occupy → occupation

permit → permission,   admit →admission,  conclude → conclusion,    decide → decision,

describe →  description   survive → survival幸存→ survivor幸存者,  

arrive → arrival,  approve → approval

perform → performance,    apologize → apology,     acquire → acquisition

apply → applicant申请人→ application-申请

to one’s  ...让某人...的是 (satisfy / astonish / annoy / amaze / disappoint / relieve / embarrass )

→satisfaction /  astonishment / annoyance / amazement / disappointment / relief /  embarrassment)  

      “in + 上述名词”，表“处于…状态”

7.名词变形容词  nature → natural,  benefit → beneficial

8.形容词变名词 wise / free →→wisdom / freedom     high /weigh→→height / weight

short/ marry →→shortage / marriage

strong/long/deep/wide/grow/dead/warm-------strength/length/depth/width/growth/death/warmth

curious/various/anxious/able/responsible/popular

→→curiosity/variety/anxiety/ability/responsibility/popularity

9. 形容词变动词

deep/ fast/ class/ identity/ beauty/ simple/ modern/ popular→→

deepen/ fasten/ classify/ identify/ beautify/simplify/modernize/ popularize

10..形容词变副词，不去e的单词(绝大多数辅音字母加e结尾的单词不去e直接加-ly)

    unfortunate →unfortunately,   immediate → immediately,

absolute→absolutely,      rude → rudely,            approximate →approximately,  

desperate→desperately,   large → largely,      accurate→ accurately

   但true-truly, whole-wholly等除外

11..形容词变副词，以ic 结尾的词，加ally

economic →economically;     basic →basically;     scientific → scientifically;

automatic →automatically;     energetic → energetically;

但是public → publicly（公开地）例外

12.容易拼写错误的单词

（1）是 or 不是er:  professor,  visitor, translator,  director, editor,  educator, actor, inventor,     competitor,  conductor  ,monitor

（2） 容易丢掉一个字母的单词
    容易丢掉字母n：government，environment，environmental
    容易丢掉不发音的字母：Christmas，  Wednesday , therefore
 （3）拼写比较特别的单词：committee委员会，guarantee担保，dilemma进退两难的困境， opportunity， bridegroom新郎，spokesman发言人，succeed，competition，February二月

13.容易多或少一个字母(括号里是错误的单词)

therefore（therefor错误）habit(habbit)   souvenir纪念品(souvenior错误)   similar  相似（simlar错误） ninth 第九（nineth错误）    forty四十（fourty错误）    healthier (healthyer错误)