英语单词中的重音是怎么规定的?是有一定规则,还是延续下来的习惯?

英语词汇的重音位置是有其规律的.
例如：有些双音节词汇做名词时重音往往落在首音节上；而做动词时,重音就落在第二音节上了.这些词汇常见的有：addict,accent,abstract,annex等.
掌握好并读准单词的重音有一定的规律可循.
为了便于记忆和学习,现将部分规则按重音位置和字母顺序作如下归纳,并从理论上进行简要分析.
一、归类部分
1．重音落在末音节的字母组合
①以-ee结尾,读音为/!>?/的词汇：
appellee chimpanzee conferee contestee decree drawee evacuee em-ployee goatee grandee guarantee indictee inductee
②以-act结尾,读音为/$kt/的词汇,多为动词：
contact contract detract distract exact enact intact interact
③-air,-aire或-are结尾,读音为/#+/的词汇：
affair concessionaire enclair millionaire aware prepare
④以-ade结尾,读音为/eid/的词汇：
arcade brigade colonnade escalade escapade（exception：decade）
⑤以-ane结尾,读音为/ein/的词汇：
inane insane profane humane
⑥以-ceive结尾,读音为/s!>?v/的动词：
conceive deceive perceive receive
⑦以-duce结尾,读音为/dj(>?s/的词汇：
conduce deduce induce introduce reduce reproduce subduce traduceseduce
⑧以-ease结尾,读音为/!>?s/或/!>?z/的词汇：
appease decease decrease disease increase predecease release sub-lease surcease
⑨以-een结尾,读音为/!>?n/的名词：
colleen canteen pretteen Salween shagreen thirteen spalpeenvelevteen yestreen
⑩以-eer结尾,读音为/i+/的名词：
cannoneer compeer domineer engineer fronteer gadgeteer gazetterpamphleteer patrioteer
(11)以-ect结尾,读音为/ekt/的动词：
affect bisect collect defect direct detect correct confect connectdisinfect eject elect
(12)以-ede结尾,读音为/!>?d/的动词：
accede antecede concede impede intercede precede recede retrocedesecede supercede
(13)以-end结尾,读音为/end/的动词：
attend amend commend comprehend contend defend depend extendintend represend subtend
(14)以-el结尾,读音为/el/的词汇：
compel impel Nobel marcel propel rebel（v．）
(15)以-ert结尾,读音为/+>?t/的词汇：
assert concert convert desert introvert subvert
(16)以-ese结尾,读/!>?s/或/!>?z/的词汇：
Chinese Japanese Napalese sudanese telegraphese vietnamese
(17)以-clude结尾,读音为/kl(>?d/的动词：
conclude exclude include occlude preclude seclude
(18)以-esce结尾,读音为/es/的词汇：
coalesce deliquesce effloresce evanesce recrudesce
(19)以-ess结尾,读音为/es/的动词：
compress confess depress express impress profess redress represssuppress transgress
若不是动词,以-ess结尾,的词汇之重音位置不固定：
'progress 'congress pro'cess un'less
(20)以-est结尾,读音为/est/的动词：
adjest congest contest digest infest protest suggest
(21)以-ette结尾,读音为/et/的词汇：
cassette cigarette brunette coquette chemisette forssette frisettegazette grisette
(22)以-form结尾,读音为/f&>?m/的动词：
conform perform reform transform（但uniform是名词）
(23)以-ict结尾,读音为/ikt/的动词：
afflict conflict constrict contradict inflict predict restric
(24)以-ide结尾,读音为/aid/的词汇：
aside astride beside confide divide provide reside subside
(25)以-ign结尾,读音为/ain/的动词：
assign condign design consign resign
(26)以-ire结尾,读音为/ai+/的动词：
conspire esquire expire desire inquire inspire require respire
(27)以-lapse结尾,读音为/l$ps/的词汇：
collapse prolapse relapse
(28)以-mit结尾,读音为/mit/的词汇：
admit commit demit emit intermit omit permit pretermit remitsubmit transmit
（若是名词,重音落在首音节,如：'limit 'summit 'vomit）
(29)以-ort结尾,读音为/&>?t/的动词：
disport distort escort export import report retort support trans-port
（若是名词,重音多落在首音节：escort export import bistort purport等.）
(30)以-ore结尾,读音为/&>?/的词汇：
afore before deplore explore restore
(31)以-pose结尾,读音为/p+us/、/p+uz/的动词：
depose decompose expose impose interpose oppose indispose predis-pose propose suppose
(32)以-scribe结尾,读音为/skraib/的词汇：
conscribe describe escribe prescribe subscribe transcribe
(33)以-scend结尾,读音为/send/的词汇：
ascend condescend descend transcend
(34)以-oon结尾,读音为/(>?n/的词汇：
afternoon balloon buffoon cartoon cocoon decocoon dragoon festoongalloon octoroon pocaroon（exception：forenoon）
(35)以-que结尾,读音为/k/的词汇：
antique boutique blottesque burlesque arabesque cacique critiquegrotesque Japanesque mystique
(36)以-r结尾,现在分词和过去分词均要双写r（-red,-ring）：
demur incur inter infer occur prefer recur refer transfer
(37)以-uct结尾,读音为/)kt/的词汇：
conduct construct deduct instruct obstruct product
(38)以-ult结尾,读音为/)lt/的词汇：
consult exult insult occult midcult result
(39)以-ume结尾,读音为/j(>?m/的词汇：
assume consume perfume presume subsume
(40)以-use结尾,读音为/j(>?s/或/j(>?z/的词汇：
accuse confuse excuse perfuse refuse suffuse transfuse
(41)以-ure结尾,读音为/ju+/的词汇：
accure impure immure insecure insure inure mature obscure per-dure procure secure（exceptions：'epicure 'manicure）
2．重音落在倒数第二个音节的字母组合：
①以-ial结尾,读音为/+l/、/i+l/或/j+l/的词汇：
/+l/：confidential decrial existential impartial inferential inffluentialinitial prejudicial sacrificial substantial
/i+l/：authorial bimestrial colloquial gressorial material mercurialministerial motorial pictorial prefatorial tectorial visitorial
/j+l/：antimonial bicentennial colonial
②以-ian结尾,读音为/+n/、/i+n/、/j+n/的词汇：
/+n/：academician arithmetician acoustician electrician Eurasian Lin-guistician musician Persian politician practician
/i+n/、/j+n/：Cantabrigian collegian Colombian historian rosarian salu-tatorian subclavian
③以-ia结尾,读音为/i+/的词汇：
国名、地名：Australia Ethiopia Indonesia Malaysia Mauritania Roma-nia
医学：abulia achromatopsia acidemia acrophobia aerophobia bilharziainsomnia
其他：academia acedia cryptomeria razzia encyclopedia
④以-ic结尾,读音为/ik/偶或包括以-ics结尾的词汇：
atomatic atmospheric autarkic autographic ballistic climatic cosmeticenteric epidemic
⑤以-ior结尾,读音为/i+/的词汇,形容词居多：
inferior junior posterior prior senior superior ulterior
⑥以-it结尾,读音为/it/的词汇：
cohabit demerit discredit discomfit decrepit deposit explicit dispiritdisinherit inspirit inherit inhabit inhibit reposit transit visit
⑦以-scence（n．）或-scent（adj）结尾：
acescence acquiescence deliquescence convalescence evanescence obso-lescence reminiscence renascence decrescent marcescent pubescent re-crudescent quiescent resipiscent suffrutescent
⑧以-ion或-sion结尾：
accusaion abolition confusion explosion decision impression persua-sion excitation suggestion invitation
3．重音落在倒数第三个音节的字母组合：
①以-fy结尾,读音为/fai/的动词：
acidify identify intensify emulsify lapidify personify qualify modifyprettify simplify transmogrify
②以-ical结尾,读音为/ik+l/的词汇：
academical chemical electrical political periodical encyclical teleologi-cal inimical theoretical technological
③以-icide结尾,读音为/isaid/的词汇：
suicide aborticide acaricide foeticide fratricide herbicide infanticideliberticide uxoricide
④以-itude结尾,读音为/itj%!d/的词汇：
attitude decrepitude infinitude lassitude latitude platitude
⑤以-ity结尾,读音为/iti/的词汇：
ability curiosity civility facility fragility opportunity personalitypossibility sensitivity simplicity speciality utility vanity whimsicality
⑥以-graph或-phy结尾,读音为/gr$f/或/fi/的词汇：
aerography bibliography biography calligraphy chirography geographylexicography photography planography telegraphy theosophy philosophy
⑦以-ology结尾,读音为/&l+d*i/的词汇：
aerology bibliology bryology crytology ecology Egyptology lexicologytechnology pestology psychology testaceology teleology theology zoology
⑧以-otomy结尾,读音为/&t+mi/的词汇：
neurotomy tenotomy tracheotomy trichotomy
⑨以-ular结尾,读音为/jul+/的词汇：
biangular binocular consular insular intercelluar ocular orbicularpopular particular secular regular triangular
4．词汇加了前缀后的重读位置
①重读落在第一音节的词汇,加前缀后,重读位置不变：
'dazzle—be'dazzle 'operate—co'operate
'force—en'force 'logical—il'logical
'literate—il'literate 'constant—in'constant
②重读落在第二音节的词汇,加前缀后,原重读位置不受影响,但前缀的字母组合作为一个音节可重读或次重读：
pro'duce—'repro'duce
'graduate—'post'graduate
'national—'inter'national
im'pressionism—'neo-imp'ressionism
（the only exception：'finite—'infinie）
二、简析部分
从语言学的角度来分析,英语的词重音（word stress）的位置是不固定的.英语与某些别的语言不同,例如：法语词汇的重音总是在词的末音节上；与法语相反的是捷克语,它的重音总是落在词的首音节上,而波兰语却独特一些,重音位置总是落在词汇的倒数第二个音节上,因此,这些语言的重音称为固定重音（fixed stress）,而英语和俄语的重音则是*重音（free stress）.英语本身吸收并借用了大量的外来语（loan words）,以历史语言学或词源学（etymology）的观点来剖析,就不难解释为什么英语重音属于*重音这一现象.例如：以-ion和-ic结尾的英语词汇重音往往落在倒数第二个音节上,而-ion和-ic结尾的字母组合则源于拉丁语.以-ee结尾的英语词汇重音总是落在末音节上,若追溯它的同源词（cognate）,我们可以看到-ee这一后缀源于Middle English的-e,而-e又来源于Middle French的-é,若再追本溯源,乃是来自于Old French的-é.再考察以-ette后缀结尾的词汇,－ette后缀也是经历了从Old French到Middle French再到Middle English这一相似的演变过程,直至现在,仍然保留了法语的重音特征,与现代法语的词重音总是落在末音节这一规律完全吻合.
以词源学的分析作为探索基点,我们认识到英语的词重音既属于*重音且并非无规律可循这一语言现象,从而对这一现象进行总结和分析,以求达到既能方便学习又能对所学语言深化理解的学习目的.