1）与endnote版牛高四的衍生、复合词entry（class=“derivative”）对比，在原始词条下找到500多个隐藏的词头，予以分离，加“★”单列独立词条。在这个过程当中，发现如下词条缺失：
address, advance, authenticate, egotistic, egotistically, flute, fluting, geological, geologically, guard, guarded, guardedly, mover, moving, movingly, potty, potty-trained, sap, sap, sap, sapper, score, scorer, singer, singing, singleness, singly, single combat, single cream, single-decker, single-handed, single-minded, single-mindedly, single-mindedness, single parent, warm, warmer, warming-pan, warm-up, wave, wavelet, wavy, wavily, waviness
从yru版牛高四中复制相应文本补充完整。
2）与yru版牛高四中的多义词词条（即末尾有1、2、3编号的词条）对比，找到下列词条及释义缺失：
accord 2| across 2| be 1| bent 2| bent 3| bid 2| book 1| burst 1| by 2| clock 2| concern 2| double 5| drip 2| edge 2| flounder 2| lighten 2| scrabble 2| scrape 2| soup 2| to 3| wage 2
乃复制相应文本补充。
此为OX-9。
牛高四文本真是一个天坑，本来我认为可能没啥大毛病了，没想到接连暴露出两个问题：一是音标转写错误，或者说不规范，不符合纸本书，原来的“乱码”音标即使使用金山音标字体，渲染出来的音标字符有些也是错的；二则是词条重复，查了一下，计有283个重复entry。
音标不规范的问题用代码+手工替换修正，冗余重复词条则一一删除。如是则有OX-8。
OX-7版对文本做了如下修订：
1）与可能的牛高四“yru版”mdx词头对比，增补近200个词头；
2）与endnote版牛高四的标准词头（standard标签）对比，修订了几十个原文中不准确的法文、西班牙文单词词头；
3）与txt81网站下载的牛高4网络文档比较，增补400多个本属于衍生词部分的词头（主要是以“-”开头的词缀和“the”开头的词组，这明显属于原发布者故意删除、破坏）；
4）遗漏的繁体字“摺”替换为“折”；
5）若干其他小错误顺手修正，比如Π、π。
OX-6版主要做的文本修订如下所述：
1）根据pdawiki网友achallan提供的单词粘连和拼写错误清单，纠正全文2000处左右此类失误。此清单难能可贵的是找出来了一些原纸本书本身（包括光盘）就有的文字讹误，计有
formly formaly responsibilty newpaper countly perfomance exultaion gentlement responsibilites continous youself mountians improbablity goverment reponsible prinicipals magnificient succesful activites spendours terrifed tranqullizing effecton regulary measureable
等。虽然纠正过程中我没有一一核对原书，但就部分核查过的单词而论，我手上的牛高4纸本也是错的。
2）在修正单词粘连错误时，发现原始txt底本存在某些词条释义不完整、被中途截断的现象，设法清查（比如用正则 [^.?!＇] \n★ 搜索），找到以下所列词条大量阙文，于是从yru版插图牛高4 mdx中补充缺失文本。
away
back bad balance bar beat beg begin believe bend best better between big bind bit bite block blow board body boil bone bottom bread break breath bring business but buy
consider
firm
nadir
quiet
spy
up use
value variety view virtue vision viz voice volume
want
3）补充全文缺失英镑符号 £ 400处左右，修正若干ä、ç、ô、∨、∧等形式的特殊符号。
OX-5版本主要集中校改因编码缘故而导致的异常字符，大概可能有500-600处（除显示为空白的，也有显示为问号的），一一根据原书校正，顺便修复了若干其他字符错误。另外，发现几处词条重复，予以删除，也有词条不完整的，如vote，根据繁体epub版补充。
1）继续纠正音标乱码修复过程中的毛病，查出上一版中未曾修正的失误有200-300个左右。
2）处理繁简转换未彻底导致的遗留事项。要说具体有多少繁体字未完成转换，不清楚，但比较明显的有“後、於、麽、著、乾、覆”等，这些字里“著”比较难对付，既作“着”用，也作“著名、著作”等用，凡3000余处。简单通改是行不通的，即使先拟定一个包含“著”的词汇表，再替换，也很容易出问题，因为文中很可能出现你假想的词汇之外其他“著”的用法，像牛高4其他版本中，有“拙着”（拙著，见immodest词条）这样的表述，而包含“著”的成语基本上全改错了。我采用的办法是通览所有3000多个含有“著”一字的句子，看看文中真正用作“著”的词汇有哪些，查找出来再遮掩住修改。词典中“著”用法的词汇统计结果如下：
著
土著 原著 著名 新著 显著 著者 著作 著称 名著 著述 巨著 拙著
臭名昭著 所著之书 恶名昭著
名声卓著 声誉卓著
3）英文不规范的引号修正。改`today’中左单引号的 ` 为 ’ ，当然，严格来说，这依然是不规范的（可搜索直引号和弯引号的区别），但起码与原文中的右单引号保持了一致。凡500余处。
想了一下，不打算修改原文中文部分所使用的标点符号，1）与纸本一致，2）数量大，容易漏改或误伤，3）算个人爱好问题，不喜欢或不习惯可以自己改。
因中文编码而引致的显示不正常字符计划下一版本修正，它数量不少，改起来要一一查书确认，比较麻烦，单独出一个版本也有利于纠谬。
《牛津高阶英汉双解词典》第4版可谓业界经典，自出版以来近30年声名不衰，迄今依然受广大英语学习爱好者追捧。其纯文本早已有好事者在网上公之于众，但品质不佳，问题甚夥，最惹眼的莫过于因使用金山音标字体导致的注音“乱码”，看着就令人闹心生厌。虽然现在此词典已有颇为完善的mdx版本，使用便捷，但纯文本文件自有其妙处，比如不受平台限制，不依赖词典软件，全文搜索方便，词条可按顺序浏览，易于转换成Word、PDF标注做笔记等，所以我计划对此文本做以校改修正，不说要多么完美，最起码基本可用吧。
校改的版本基础为我早年收集的缺少“L”词条的TXT文件，其缺失内容从 http://www.txt81.com/down/4740.html 处的文档补充，不直接使用此网站文件是因为它存在一些缺陷，例如音标里的US字样被删除，部分英文单词间的空格消失。不过这个网络文档也有一些长处，比如某些以the开头的词条（the unconscious等）在我的文件里没有，它却是完整的，以后可以通过对比补充找回。
此最基础的底本我称之为OX.txt，其后校改更正过版本会依序命名为OX-1、OX-2……OX-n等，在此首先贴出的版本是OX-3.txt.
OX-3在原始底本（OX.txt）上做了以下修正：
1）校正音标乱码。修改的办法是先用程序，谨慎使用正则，以免过多误伤，但因为谨慎，会导致少量音标乱码没有被改正，于是再用正则查找手工纠正。尽管如此，以我的经验，正则批量修改肯定会出想不到的意外，一种是误伤，修改了不是音标的字符，一种是仍然有躲藏着没被修正的音标，抽样目测了一下，这种情况还是比较少的，在可接受范围以内。
2）完善词头（headword）标签。在词典纯文本文件里，把词头全部标注清楚是比较重要的，不然混在正文中很难进一步加工，就是阅读也困难，找不到重点目标所在。原始文件本身在词头前有“★”标签，但遗漏很多，于是设法（正则查找+目测检视等）一一补充，目前得词头44060个。可能继续会有遗漏，应该很少。
以我的标准，经过如上修正，OX-3算勉强可用，最起码没有无数音标乱码闹心碍眼了，在chrome、VS code或者Notepad++里打开全文浏览、搜索，是比较方便的。
在这里发布的版本（OX-3）只是计划中一系列修正的起点，目前我想到的还可以继续校改的问题有：
a、纠正上一步音标和标签修改中的错误。
b、处理繁简转换导致的错误，像“後、於、麽、著、乾”等。
c、英文引号标点混乱纠正。比如 In the word `today’ the accent is on the second syllable. ——`today’前的字符并不是正规的英文引号，但它不是简单替换就能修正的，因为词典中原先音标里的重音，正文短语里标注重音，用的是同样的符号。怎么只修改引号用法的`，而不伤其他令人头痛。
d、修正中文标点。是否把原文中不规范的中文引号（‘ ’）、句号（.)修改过来，此点待议。
e、纠正中文当中可能因为编码问题导致的错误。原文中有些字符显示不正常，比如“错误地或愚 地付出（爱情、 情感等）”，这里空格处应该是“昧”，但却编码为 E38080 ，UTF-8内码无法显示。粗略搜了一下，类似的地方有300余处。
f、修正原词典文本本身可能就有的讹误。在这里freemidct论坛的帖子（ https://forum.freemdict.com/t/topic/3861 ）就有很多可借鉴之处。
g、补充在开头已经提到过的遗漏缺失词条。
有其他未及事项，网友可补充。
与我收集的某一牛高4 mdx（可能是yru版）解出文本（ 见 https://github.com/mahavivo/english-dictionary/tree/master/OALD4 ）程序对比，加人工核实，初步统计校改文本缺失词头（headword）如下所列：
acerbic | acetic | -ade | adjacent | admonish | aftermath | afters | -age | AIDS | -al | -an | -ana | -ance, -ence | -ancy, -ency | aniseed | -ant, -ent | anticipation | antiknock | antimony | antipathy | arcane | -ard | -arian | artisan | artiste | -ary | -ate | -ation | -ative | -ator | augur | august | August | auricle | auriferous | balls | bead | become | -bellied | besom | biceps | biro | birthday | bisect | -bodied | bop | buckler | by- | carcinogen | cheers | cheery | -cide | cirrhosis | cirrus | cissy | Cistercian | cistern | citadel | cite | comely | contentious | contest | context | CONTRA | COORDINATE | CO-ORDINATE | -cracy | -crat | -cy | -d | Dail Eireann | despot | -dom | -ectomy | -ed | -ee | -eer | 'em | embrace | -en | -ence | -ent | -er | -ery | -ese | -esque | -ess | -ette | -ey | falsetto | falsify | federal | fo’c’s’le | -fold | fortunate | -ful | future | -fy | -gamy | garlic | gnome | -gon | -gram | gram | -graph | -graphy | gully | ha’p’orth | -hood | hormone | -ial | -ian | -iana | -iatrics | -iatry | -ible | -ic | -ics | -ide | -ie | -ify | -in | indispensable | indoors | institution | instruct | -ion | -ise | -ish | -ism | -ist | -ite | -ition | -itis | -ity | -ive | -ize, -ise | L/Cpl | lights | -mania | -ment | metallurgy | -meter | -metre | misgovern | -most | mynah | ne’er | ne’er-do-well | -ness | -oid | op cit | -or | -ory | -ous | overshoot | PARA | -path | -pathy | -philia | -phobia | -phone | prepuce | re-cover | ritual | ruble | -ry | -scape | -scope | -ship | -shooter | -sion | -some | -speak | -sphere | -ster | sulfide | syndrome | -th | times | -tion | toccata | toils | 'un | -ure | Virginia `creeper | vv | -ward | -ways | -wise | -xion | -y | -acy
计193个。这些词头里比较瞩目的是become这么基本的词汇也丢失了。
与endnote 2022新春版mdx对比，去除和“yru版”重复的数据后，单独查核出来的的“缺失”词头如下：
-able | -acy | agr- | aide-mémoire | -ance | -ancy | -ant | anthrop- | appliqué | après-ski | arête | attaché | aut- | blasé | bric-à-brac, bric-a-brac | bête noire | café, cafe | canapé | cardi- | cent- | chargé d’affaires | chron- | château | cliché | communiqué | compère, compere | consommé | coupé | crypt- | crème de la crème | crème de menthe | débutante | début | dem- | derm- | diamanté | débâcle, debacle | décolleté | décor, decor | déjà vu | démarche, demarche | déshabillé | détente | electr- | entrepôt, entrepot | entrée, entree | Eur- | exposé, expose | façade, facade | flambé | fête, fete | glacé | -graphical | gruyère | habitué | hect- | hex- | -ian | ingénue, ingenue | -ion | is- | -ize | kümmel | lycée | manqué | matinée | -metre | mise-en-scène | mélange | ménage, menage | mésalliance | métier | mêlée, melee | necr- | neur- | née, nee | orth- | outré | pant- | passé | path- | phil- | phon- | physi- | pied-à-terre | pietà | pièce de rèsistance | première, premiere | prot- | précis | pseud- | psych- | pâté | quadr- | raison d’être | recherché | retroussé | risqué | rosé | roué | résumé | röntgen | sauté | sept- | señor | soigné | soirée, soiree | son et lumière | table d’hôte | tel- | tetr- | the- | therm- | touché | tête-a-tête | Virginia creeper | vis-à-vis | à la carte | à la mode | éclair | éclat | élite, elite | émigré, emigré | épée, epee
共计124个。不过值得注意的此处很多“缺失”词头其实在原文中不缺，只是拼写有异，没有用正确的法文字符。
按照endnote版mdx初步统计，牛高4共有标准词头22206个，习语7755个，动词短语2963个，衍生词、复合词18565个。查yru版mdx，共有词头22640个。标准词头的统计、对比和查漏相对容易，但限于牛高4原始文本的形式（没有数据库化，也没有特别标签，词组中还夹杂有重音符号等），衍生词-复合词，习语，动词短语要一一准确对比和查漏比较困难。
与主帖中所述及牛高4网络文档比较，初步统计校改文本缺少如下词头，共计478个，主要归属于衍生词部分，明显是原制作发布者故意删除。
-ability, -ibility | -ability, -ibility | -able, -ible | -able, -ible | -ably, -ibly | -acy | -ade | -age | -al | -ally | -an | -ana | -ance, -ence | -ance, -ence | -ancy, -ency | -ancy, -ency | -ant, -ent | -ant, -ent | -ard | -arian | -ary | -ary | -ate | -ately | -ation | -ative | -atively | -ator | -bedded | -behaved | -bellied | -bellied | -bodied | -born | -bound | -brimmed | -burger | -cheeked | -chested | -cidal | -cide | -cornered | -cracy | -craft | -crat | -cratic | -cy (also -acy) | -d | -decker | -deep | -dimensional | -dom | -eared | -ectomy | -ed (also -d) | -edged | -ee | -eer | -en | -ence | -ent | -er | -ery (also -ry) | -ese | -esque | -ess | -ess | -ette | -ey | -eyed | -faced | -faceted | -fired | -flavoured (US -flavored) | -fold | -footed | -footed | -footer | -footer | -former | -free | -friendly | -ful | -fy | -gamous, -gamously | -gamy | -goer | -gon | -gonal | -grained | -gram | -graph | -grapher | -graphic(al) | -graphy | -haired | -handed | -handled | -headed | -hearted | -heeled | -hipped | -hood | -hued | -humoured (US -humored) | -ial | -ially | -ian (also -an) | -iana (also -ana) | -iatric | -iatric, -iatrical | -iatrics | -iatry | -ible | -ic | -ical | -ical | -ically | -ics | -ide | -ie | -ify (also -fy) | -ily | -in | -in-chief | -iness | -intensive | -intentioned | -ion (also -ation, -ition, -sion, -tion, -xion) | -ise | -ise, -ize | -ish | -ism | -ist | -ist | -ite | -ition | -itis | -ity | -ive | -ization, -isation | -izationally, -isationally | -ize, -ise | -man | -man | -mania | -maniac | -mannered | -manship | -manship | -masted | -ment | -mental | -mentally | -mentioned | -meter | -metre (US -meter) | -most | -mouthed | -natured | -ness | -nosed | -oid | -orientated | -ory | -ous | -path | -path | -pathic | -pathy | -phile (also -phil) | -philia | -philiac | -phobe | -phobia | -phobic | -phone | -phonic | -pronged | -raiser | -resistant | -rimmed | -roomed | -ry | -saving | -scape | -scope | -scopic(al) | -scopy | -seater | -sexed | -shaped | -ship | -shooter | -shy | -sick | -sided | -sighted | -sion | -sized | -skinned | -skulled | -sleeved | -soled | -some | -sounding | -speak | -sphere | -spheric (also -spherical) | -spirited | -spoken | -stemmed | -ster | -suited | -syllabled | -tailed | -tasting | -tempered | -th | -throated | -tiered | -tion | -toned | -tongued | -ure | -voiced | -waisted | -ward | -wards (also esp US -ward) | -ways | -wheeled | -wheeler | -wide | -willed | -wise | -witted | -woman | -worthy | -xion | -y | -y (also -ey)
the ,South Pole | the ,Supreme Being | the Almighty | the Antarctic | the Antarctic Circle | the Arctic | the Arctic Circle | the Ark of the Covenant | the Authorized Version | the Black Country | the Black Death | the Blessed | the Blessed Sacrament | the British | the British Isles | the Broads | the Bronze Age | the Christian Era | the Church of England | the Civil Service | the Common Market (also the European EconomicCommunity) | the Communist Party | the Conservative Party | the Coptic Church | the Corn Laws | the Dark Ages | the Dark Continent | the East End | the Eastern Bloc | the English Channel (also the Channel) | the Eternal City | the European Economic Community (abbr 缩写 EEC) | the Far East | the Far West | the First World War (also World War I) | the Foreign and Commonwealth Office (abbr 缩写 FCO) | the Grand National | the Great Bear | the Great Lakes | the Great War | the Green Party | the Gulf Stream | the Holy City | the Holy Father | the Holy Ghost | the Holy Grail | the Holy Land | the Holy See | the Holy Spirit (also the Holy Ghost) | the Home Counties | the Home Guard | the Home Office | the House of Commons (also the Commons) | the House of Lords (also the Lords) | the House of Representatives | the Houses of Parliament | the Immaculate Conception | the Industrial Revolution | the Infinite | the Iron Age | the Iron Curtain | the Jolly Roger | the Last Judgement | the Last Supper | the Metropolitan Police (also the Met) | the Middle Ages | the Middle East | the Middle West | the Midlands | the Midwest | the Milky Way | the National Debt | the New Testament | the New World | the North Country | the North Pole | the Old Testament | the Old World | the Olympic Games | the Open University | the Orthodox Church (also The Eastern Orthodox Church) | the Peak District | the Pilgrim Fathers (also the Pilgrims) | the Pleistocene | the Pliocene | the Press Association (abbr 缩写 PA) | the Queen’s English | the Redeemer | the Revised Standard Version | the Roman alphabet | the Security Council | the Social and Liberal Democrats (abbr 缩写 SLD) | the Son of God, the Son of Man | the Spanish Main | the Stars and Stripes | the State Department | the Stone Age | the Supreme Court | the Supreme Soviet | the Union Jack (also the Union flag) | the United Kingdom (abbr 缩写 (the) UK) | the United Nations (abbr 缩写 (the) UN) | the United States (of America) (abbrs 缩写 (the) US, USA) | the Upper Chamber (also the Upper House) | the West Country | the West End | the White House | the Wild West | the women's movement | the absolute | the accused | the ancients | the armed forces, the armed services | the assured | the beau monde | the bereaved | the blind | the body politic | the burden of proof | the class struggle (also the class war) | the damned | the deceased | the deep South | the departed | the dispossessed | the dog-star | the elect | the electric chair | the evening star | the fair sex | the faithful | the fallen | the few | the fine print | the first person | the foregoing | the former | the front bench | the front line | the generation gap | the golden mean | the gripes | the handicapped | the high jump | the high sea (also the high seas) | the holy of holies | the home front | the home straight (also esp US the home stretch) | the homeless | the human race | the impossible | the inevitable | the infirm | the initiated | the insane | the insured | the jet set | the jitters | the just | the kiss of life | the last post | the last rites | the many | the metric system | the middle distance | the midnight sun | the military | the missing | the money supply | the morning star | the next | the northern lights | the occult | the old | the old country | the old guard | the once | the open | the open sea | the open season | the oppressed | the poor | the priesthood | the rag trade | the rank and file | the ravages | the rich | the rising generation | the roadway | the sack | the sack | the safe period | the same | the sandman | the second coming | the seventh day | the small hours | the solar system | the solar year | the sterling area | the sulks | the supernatural | the synoptic gospels | the unconscious | the undermentioned | the underprivileged | the undersigned | the unemployed | the unexpected | the unwaged | the unwary | the utmost (also the uttermost) | the vitals | the weak | the wicked | the working class (also the working classes) | the yellow press
(right) up one’s street | April Fool’s Day | L/Cpl | Virginia creeper | a few | a fifth column | a gentleman’s agreement | a mite | a sword of Damocles | agitation | askance (at sb/sth) | be taken with sb/sth | cent(i) | incompre-hensibly | lawcourt (also court of law) | like a ton of bricks | make bricks without straw | on the quiet | take the bread out of sb's mouth | will-o-the-wisp