Phonological history of English

The phonological history of English describes the changing phonology of the English language over time, starting from its roots in proto-Germanic to diverse changes in different dialects of modern English.

NOTE: In the following description, abbreviations are used as follows:

  • C = any consonant
  • V = any vowel
  • # = end of word
  • * = reconstructed
  • ** = non-existent
  • > = changes into
  • >! = changes into, unexpectedly
  • < = is derived from

Changes by time period

This section summarizes the changes occurring within distinct time periods, covering the last 2,000 years or so. Within each subsection, changes are in approximate chronological order.

The time periods for some of the early stages are quite short due to the extensive population movements occurring during the Migration Period (early AD), which resulted in rapid dialect fragmentation.

Late Proto-Germanic period

This period includes changes in late Proto-Germanic, up to about the 1st century. Only a general overview of the more important changes is given here; for a full list, see the Proto-Germanic article.

Northwest Germanic period

This was the period that existed after the East Germanic languages had split off. Changes during this time were shared with the North Germanic dialects, i.e. Proto-Norse. Many of the changes that occurred were areal, and took time to propagate throughout a dialect continuum that was already diversifying. Thus, the ordering of the changes is sometimes ambiguous, and can differ between dialects.

West Germanic period

This period occurred around the 2nd to 4th centuries. It is unclear if there was ever a distinct "Proto-West Germanic", as most changes in this period were areal, and likely spread throughout a dialect continuum that was already diversifying further. Thus, this "period" may not have been a real timespan, but may simply cover certain areal changes that did not reach into North Germanic. This period ends with the further diversification of West Germanic into several groups before and during the Migration Period: Ingvaeonic, Istvaeonic (Old Frankish) and Irminonic (Upper German).

Ingvaeonic and Anglo-Frisian period

This period is estimated to have lasted only a century or so, the 4th to 5th; the time during which the Franks started to spread south into Gaul (France) and the various coastal people began colonising Britain. Changes in this period affected the Ingvaeonic languages, but not the more southerly Central and Upper German languages. The Ingvaeonic group was probably never homogeneous, but was divided further into Old Saxon and Anglo-Frisian. Old Frankish (and later Old Dutch) was not in the core group, but was affected by the spread of several areal changes from the Ingvaeonic area.

The Anglo-Frisian languages shared several unique changes that were not found in the other West Germanic languages. The migration to Britain caused a further split into early Old English and early Old Frisian.

Old English period

This period is estimated to be c. AD 475–900. This includes changes from the split between Old English and Old Frisian (c. AD 475) up through historic early West Saxon of AD 900:

Until Middle English

This period is estimated to be c. AD 900–1400.

Up to Shakespeare's English

This period is estimated to be c. AD 1400–1600.

Up to the American–British split

This period is estimated to be c. AD 1600–1725.

After American–British split, up to the 20th century

This period is estimated to be c. AD 1725–1900.

After 1900

Some of these changes are in progress.

Examples of sound changes

The following table shows a possible sequence of changes for some basic vocabulary items, leading from Proto-Indo-European (PIE) to Modern English. The notation ">!" indicates an unexpected change, whereas the simple notation ">" indicates an expected change. An empty cell means no change at the given stage for the given item. Only sound changes that had an effect on one or more of the vocabulary items are shown.

one two three four five six seven mother heart hear
Proto-Indo-European óynos dúoH tríh₂ (fem.) kʷetwṓr pénkʷe séḱs septḿ̥ méh₂tēr ḱḗr h₂ḱowsyónom
Pre-Germanic unexpected changes >! dwóy >! tríh₂s >! petwṓr >! pémpe >! sepḿ̥d >! meh₂tḗr >! kérdō
Sonorant epenthesis sepúmd
Final overlong vowels kérdô
Laryngeal loss trī́s mātḗr kowsyónom
Loss of final nonhigh vowels pemp
Grimm's Law twoi þrī́s feþwṓr fémf sehs sefúmt māþḗr hértô housjónom
Verner's Law oinoz þrīz feðwōr seβumt māðēr houzjonom
o > a, ō > ā, ô > â ainaz twai feðwār hertâ hauzjanam
Final -m > -n hauzjanan
m > n before dental seβunt
Final -n > nasalization hauzjaną
Loss of final -t seβun
Sievers' Law hauzijaną
Nasal raising fimf
ā > ō, â > ô feðwōr mōðēr hertô
Proto-Germanic form ainaz twai þrīz feðwōr fimf sehs seβun mōðēr hertô hauzijaną
Final vowel shortening/loss ainz? þrīz feðwur mōðar hertō hauzijan
Final -z loss ain þrī
Rhotacism: z > r haurijan
Intervocalic ðw > ww fewwur
Hardening: ð > d, β > v, f [ɸ] > [f] finf sevun mōdar
Morphological changes >! þriju >! herta
West Germanic pre-form ain twai þriju fewwur finf sehs sevun mōdar herta haurijan
Ingvaeonic (prespirant) nasal loss fīf
ai > ā ān twā
Anglo-Frisian brightening hertæ hæurijan
I-mutation heyrijan
Loss of medial -ij- heyran
Breaking hĕŭrtæ
Diphthong height harmony feowur hĕŏrtæ hēran, hiyran
Back mutation sĕŏvun
Final reduction feowor sĕŏvon >! mōdor hĕŏrte
Raising: ehs eht > ihs iht sihs
hs > ks siks
Late OE lowering: iu > eo þreo
iy > ȳ hȳran
Late Old English spelling ān twā þrēo fēowor fīf six seofon mōdor heorte hēran, hȳran
Middle English (ME) smoothing θrøː føːwor søvon hørte
ME final reduction føːwǝr søvǝn moːdǝr hørtǝ heːrǝn
ME a: æ: > ɔ: ɛ: ɔːn twɔː
-dǝr > -ðǝr moːðǝr
ME unexpected (?) vowel changes >! fiːv-ǝ >! hɛːrǝn
ME diphthong changes >! fowǝr
Late ME unrounding θreː sevǝn hertǝ
Late Middle English spelling (c. 1350) oon two three fower five six seven mother herte heere(n)
Late ME final reduction (late 1300s) >! fowr fiːv hert hɛːr
Late ME /er/ > /ar/ (1400s)[26] hart
Late ME Great Vowel Shift (c. 1400-1550) oːn >! wʊn twoː θriː fǝiv muːðǝr heːr
Early Modern English (EModE) smoothing foːr
EModE raising /woː/ > /wuː/ > /uː/[27] tuː
EModE shortening mʊðǝr
EModE /ʊ/ > /ʌ/ wʌn mʌðǝr
Later vowel shifts fɔːr faiv sɪks hɑrt hiːr
Loss of -r (regional) fɔː mʌðǝ hɑːt hiǝ
Modern pronunciation wʌn tuː θriː fɔː(r) faiv sɪks sevǝn mʌðǝ(r) hɑrt/hɑːt hiːr/hiǝ
one two three four five six seven mother heart hear

NOTE: Some of the changes listed above as "unexpected" are more predictable than others. For example:

Summary of vowel developments

Development of Middle English vowels


This table describes the main historical developments of English vowels in the last 1000 years, beginning with late Old English and focusing on the Middle English and Modern English changes leading to the current forms. It provides a lot of detail about the changes taking place in the last 600 years (since Middle English), while omitting any detail in the Old English and earlier periods. For more detail about the changes in the first millennium AD, see the section on the development of Old English vowels.

This table omits the history of Middle English diphthongs; see that link for a table summarizing the developments.

The table is organized around the pronunciation of Late Middle English c. 1400 AD (the time of Chaucer) and the modern spelling system, which dates from the same time and closely approximates the pronunciation of the time. (Modern English spelling originates in the spelling conventions of Middle English scribes and its modern form was largely determined by William Caxton, the first English printer (beginning in 1476).

As an example, the vowel spelled a corresponds to two Middle English pronunciations: /a/ in most circumstances, but long /aː/ in an open syllable, i.e. followed by a single consonant and then a vowel, notated aCV in the spelling column. (This discussion ignores the effect of trisyllabic laxing.) The lengthened variant is due to the Early Middle English process of open-syllable lengthening; this is indicated by (leng.). Prior to that time, both vowels were pronounced the same, as a short vowel /a/; this is reflected by the fact that there is a single merged field corresponding to both Middle English sounds in the Late Old English column (the first column). However, this earlier Middle English vowel /a/ is itself the merger of a number of different Anglian Old English sounds:

  1. the short vowels indicated in Old English spelling as a, æ and ea;
  2. the long equivalents ā, ēa, and often ǣ when directly followed by two or more consonants (indicated by ā+CC, ǣ+CC, etc.);
  3. occasionally, the long vowel ē when directly followed by two consonants, particularly when this vowel corresponded to West Saxon Old English ǣ. (Middle English, and hence Modern English, largely derives from the Anglian dialect of Old English, but some words are derived from the West Saxon dialect of Old English, because the border between the two dialects ran through the London area. Note that the West Saxon dialect, not the Anglian dialect, is the "standard" dialect described in typical reference works on Old English.)

Moving forward in time, the two Middle English vowels /a/ and /aː/ correspond directly to the two vowels /a/ and /ɛː/, respectively, in the Early Modern English of c. 1600 AD (the time of Shakespeare). However, each vowel has split into a number of different pronunciations in Modern English, depending on the phonological context. The short /a/, for example, has split into seven different vowels, all still spelled a but pronounced differently:

  1. /æ/ when not in any of the contexts indicated below, as in man, sack, wax, etc.
  2. A vowel pronounced /ɑ/ in General American (GA) and /ɒ/ in Received Pronunciation (RP) when preceded by /w/ and not followed by the velar consonants /k/, /ɡ/ or /ŋ/, as in swan, wash, wallow, etc. (General American is the standard pronunciation in the U.S. and Received Pronunciation is the most prestigious pronunciation in Britain. In both cases, these are the pronunciations typically found in news broadcasts and among the middle and upper classes.)
  3. /ɑr/ (GA) or /ɑː/ (RP) when followed by a written r, as in hard, car, etc. (Note, this does not include words like care, where the a was pronounced as long /aː/ in Middle English.)
  4. But /ɔr/ (GA) or /ɔː/ (RP) when both preceded by /w/ and followed by written r, as in war, swarm, etc.
  5. /ɔː/ when followed by an /l/ plus either a consonant or the end of a word, as in small, walk, etc. (In the case of walk, talk, chalk, etc. the /l/ has dropped out, but this is not indicated here. Note also that words like rally, shallow and swallow are not covered here because the /l/ is followed by a vowel; instead, earlier rules apply. Nor are words like male covered, which had long /aː/ in Middle English.)
  6. /ɑ/ (GA) or /ɑː/ (RP) when followed by /lm/, as in palm, calm, etc. (Note that the /l/ has dropped out in pronunciation.)
  7. In RP only, the pronunciation /ɑː/ is often found when followed by an unvoiced fricative, i.e. /f/, /s/ or /θ/, as in glass, after, path, etc. This does not apply to GA and also unpredictably does not affect a number of words of the same form, e.g. crass, math, etc.

NOTE: In this table, abbreviations are used as follows:

Late Old English (Anglian), c. 1000 Middle English pronunciation, c. 1400 Modern English spelling, c. 1500 Early Modern English pronunciation, c. 1600 Modern English pronunciation, c. 2000 Source Example
a; æ; ea; ā+CC; often ǣ+CC,ēa+CC; occ. ē+CC (WS ǣ+CC) /a/ a /a/ /æ/ OE a OE mann > man; OE lamb > lamb; OE sang > sang; OE sacc > sack; OE assa > ass (donkey)
OE æ OE fæþm embrace > fathom; OE sæt > sat; OE æt > at; OE mæsse > mass (at church)
OE ea OE weax > wax; OE healf > half /hæf/ (GA)
OE +CC OE āscian > ask /æsk/ (GA); OE fǣtt > fat; OE lǣstan > to last /læst/ (GA) ; OE blēddre (WS blǣddre) > bladder; OE brēmbel (WS brǣmbel) > bramble
(w+, not +g,ck,ng,nk) GA /ɑ/, RP /ɒ/ OE a OE swan > swan; OE wasċan > to wash; OE wann dark > wan
OE æ OE swæþ > swath; OE wæsp > wasp
OE ea OE wealwian > to wallow; OE swealwe > swallow (bird)
(+r) /ar/ > GA /ɑr/, RP /ɑː/ OE heard > hard; OE ærc (WS earc) > ark
(w+ and +r) /ɔr/ > GA /ɔr/, RP /ɔː/ OE ea OE swearm > swarm; OE sweart > old poetic swart >! swarthy; OE weardian > to ward; OE wearm > warm; OE wearnian > to warn
(+lC,l#) /ɔː/ OE smæl > small; OE all (WS eall) > all; OE walcian (WS wealcian) to roll > to walk
(+lm) GA /ɑ/, RP /ɑː/ OE ælmesse > alms; Latin palma > OE palm > palm
(RP, often +f,s,th) /ɑː/ OE glæs > glass; OE græs > grass; OE pæþ > path; OE æfter > after; OE āscian /ɑːsk/ > to ask; OE lǣstan /lɑːst/ > to last
(leng.) /aː/ [æː] aCV /ɛː/ /eː/ > /ei/ OE a OE nama > name; OE nacod > naked; OE bacan > to bake
OE æ OE æcer > acre; OE hwæl > whale; OE hræfn > raven
(+r) /eːr/ > GA /ɛr/, RP /ɛə/ OE a OE caru > care; OE faran > to fare; OE starian > to stare
e; eo; occ. y; ē+CC; ēo+CC; occ. ǣ+CC,ēa+CC /e/ e /ɛ/ /ɛ/ OE e OE helpan > to help; OE elh (WS eolh) > elk; OE tellan > to tell; OE betera > better; OE streċċan > to stretch
OE eo OE seofon > seven
OE y OE myriġ > merry; OE byrġan > to bury /bɛri/; OE lyft- weak > left (hand); OE cnyll > knell
OE +CC OE cēpte > kept; OE mētte > met; OE bēcnan (WS bīecnan) > to beckon; OE clǣnsian > to cleanse; OE flǣsċ > flesh; OE lǣssa > less; OE frēond > friend /frɛnd/; OE þēofþ (WS þīefþ) > theft; OE hēold > held
(+r) ar /ar/ GA /ɑr/, RP /ɑː/ OE heorte > heart; OE bercan (WS beorcan) > to bark; OE teoru (WS teru) > tar; OE steorra > star
(w+ and +r) /ɔr/ > GA /ɔr/, RP /ɔː/ AN werra > war; AN werbler > to warble
(occ. +r) er /ɛr/ /ər/ > GA /ər/, RP /ɜː/ OE e OE sterne (WS stierne, styrne) > stern
OE eo OE eorl > earl; OE eorþe > earth; OE liornian, leornian > to learn
OE +CC OE hērde (WS hīerde) > heard
(leng.) /ɛː/ ea,eCV /eː/ /iː/ OE specan > to speak; OE mete > meat; OE beofor > beaver; OE meotan (WS metan) > to mete /miːt/; OE eotan (WS etan) > to eat; OE meodu (WS medu) > mead; OE yfel > evil
(+r) /iːr/ > GA /ɪr/, RP /ɪə/ OE spere > spear; OE mere > mere (lake)
(occ.) /ei/ OE brecan > to break /breik/
(occ. +r) /eːr/ > GA /ɛr/, RP /ɛə/ OE beoran (WS beran) > to bear; OE pere, peru > pear; OE swerian > to swear; OE wer man > were-
(often +th,d,t,v) /ɛ/ OE leþer > leather /lɛðɚ/; OE stede > stead; OE weder > weather; OE heofon > heaven; OE hefiġ > heavy
i; y; ī+CC,ȳ+CC; occ. ēoc,ēc; occ. ī+CV,ȳ+CV /i/ i /ɪ/ /ɪ/ OE i OE writen > written; OE sittan > to sit; OE fisċ > fish; OE lifer > liver
OE y OE bryċġ > bridge; OE cyssan > to kiss; OE dyde > did; OE synn > sin; OE gyldan > to gild; OE bysiġ > busy /bɪzi/
OE +CC OE wīsdōm > wisdom; OE fīftiġ > fifty; OE wȳsċan > to wish; OE cȳþþ(u) > kith; OE fȳst > fist
OE ȳ+CV,ī+CV OE ċīcen > chicken; OE lȳtel > little
OE ēoc,ēc OE sēoc > sick; OE wēoce > wick; OE ēc + nama > ME eke-name >! nickname
(+r) /ər/ > GA /ər/, RP /ɜː/ OE gyrdan > to gird; OE fyrst > first; OE styrian > to stir
(leng. occ.) /eː/ ee /iː/ /iː/ OE wicu > week; OE pilian > to peel; OE bitela > beetle
o; ō+CC /o/ o /ɔ/ GA /ɑ/, RP /ɒ/ OE o OE god > god; OE beġeondan > beyond
OE +CC OE gōdspell > gospel; OE fōddor > fodder; OE fōstrian > to foster
(GA, +f,s,th,g,ng) /ɔː/ OE moþþe > moth; OE cros > cross; OE frost > frost; OE of > off; OE oft > oft; OE sōfte > soft
(+r) /ɔr/ > GA /ɔr/, RP /ɔː/ OE corn > corn; OE storc > storc; OE storm > storm
(leng.) /ɔː/ oa,oCV /oː/ GA /ou/, RP /əu/ OE fola > foal; OE nosu > nose; OE ofer > over
(+r) /oːr/ > GA /ɔr/, RP /ɔː/ OE borian > to bore; OE fore > fore; OE bord > board
u; occ. y; ū+CC; w+ e,eo,o,y +r /u/ u,o /ʊ/ /ʌ/ OE u OE bucc > buck /bʌk/; OE lufian > to love /lʌv/; OE uppe > up; OE on bufan > above
OE y OE myċel > ME muchel >! much; OE blysċan > to blush; OE cyċġel > cudgel; OE clyċċan > to clutch; OE sċytel > shuttle
OE +CC OE dūst > dust; OE tūsc > tusk; OE rūst > rust
(b,f,p+ and +l,sh) /ʊ/ OE full > full /fʊl/; OE bula > bull; OE bysċ > bush
(+r) /ər/ > GA /ər/, RP /ɜː/ OE u OE spurnan > to spurn
OE y OE ċyriċe > church; OE byrþen > burden; OE hyrdel > hurdle
OE w+,+r OE word > word; OE werc (WS weorc) > work; OE werold > world; OE wyrm > worm; OE wersa (WS wiersa) > worse; OE weorþ > worth
(leng. occ.) /oː/ oo /uː/ /uː/ OE (brȳd)-guma > ME (bride)-gome >! (bride)-groom
(+r) /uːr/ > /oːr/ > GA /ɔr/, RP /ɔː/ OE duru > door
(often +th,d,t) /ʌ/ ?
(occ. +th,d,t) /ʊ/ OE wudu > wood /wʊd/
ā; often a+ld,mb /ɔː/ oa,oCV /oː/ GA /ou/, RP /əu/ OE ā OE āc > oak; OE hāl > whole
OE +ld,mb OE camb > comb; OE ald (WS eald) > old; OE haldan (WS healdan) > to hold
(+r) /oːr/ > GA /ɔr/, RP /ɔː/ OE ār > oar, ore; OE māra > more; OE bār > boar; OE sār > sore
ǣ; ēa /ɛː/ ea,eCV /eː/ /iː/ OE ǣ OE hǣlan > to heal /hiːl/; OE hǣtu > heat; OE hwǣte > wheat
OE ēa OE bēatan > to beat /biːt/; OE lēaf > leaf; OE ċēap > cheap
(+r) /iːr/ > GA /ɪr/, RP /ɪə/ OE rǣran > to rear ; OE ēare > ear; OE sēar > sere; OE sēarian > to sear
(occ.) /ei/ OE grēat > great /greit/
(occ. +r) /eːr/ > GA /ɛr/, RP /ɛə/ OE ǣr > ere (before)
(often +th,d,t) /ɛ/ OE ǣ OE brǣþ odor > breath; OE swǣtan > to sweat; OE -sprǣdan > to spread
OE ēa OE dēad > dead /dɛd/; OE dēaþ death; OE þrēat menace > threat; OE rēad > red; OE dēaf > deaf
ē; ēo; often e+ld /eː/ ee,ie(nd/ld) /iː/ /iː/ OE ē OE fēdan > to feed; OE grēdiġ (WS grǣdiġ) > greedy; OE > me; OE fēt > feet; OE dēd (WS dǣd) > deed; OE nēdl (WS nǣdl) > needle
OE ēo OE dēop deep; OE fēond > fiend; OE betwēonum > between; OE bēon > to be
OE +ld OE feld > field; OE ġeldan (WS ġieldan) to pay > to yield
(often +r) /ɛːr/ ear,erV /eːr/ /iːr/ > GA /ɪr/, RP /ɪə/ OE ē OE hēr > here; OE hēran (WS hīeran) > to hear; OE fēr (WS fǣr) > fear
OE ēo OE dēore (WS dīere) > dear
(occ.) /eːr/ > GA /ɛr/, RP /ɛə/ OE þēr (WS þǣr) > there; OE hwēr (WS hwǣr) > where
(occ. +r) /eːr/ eer /iːr/ /iːr/ > GA /ɪr/, RP /ɪə/ OE bēor > beer; OE dēor > deer; OE stēran (WS stīeran) > to steer; OE bēr (WS bǣr) > bier
ī; ȳ; often i+ld,mb,nd; often y+ld,mb,nd /iː/ i,iCV /əi/ /ai/ OE ī OE rīdan > to ride; OE tīma > time; OE hwīt > white; OE mīn > mine (of me)
OE ȳ OE mȳs > mice; OE brȳd > bride; OE hȳdan > to hide
OE +ld,mb,nd OE findan > to find; OE ċild > child; OE climban > to climb; OE mynd > mind
(+r) /air/ > GA /air/, RP /aiə/ OE fȳr > fire; OE hȳrian > to hire; OE wīr > wire
ō; occ. ēo /oː/ oo /u:/ /u:/ OE ō OE mōna > moon; OE sōna > soon; OE fōd > food /fuːd/; OE dōn > to do
OE ēo OE cēosan > to choose; OE sċēotan > to shoot
(+r) /uːr/ > /oːr/ > GA /ɔr/, RP /ɔː/ OE flōr > floor; OE mōr > moor
(occ. +th,d,v) /ʌ/ OE blōd > blood /blʌd/; OE mōdor > mother /mʌðə(r)/; OE glōf > glove /glʌv/
(often +th,d,t,k) /ʊ/ OE gōd > good /gʊd/; OE bōc > book /bʊk/; OE lōcian > to look /lʊk/; OE fōt > foot /fʊt/
ū; often u+nd /uː/ ou /əu/ /au/ OE ū OE mūs > mouse; OE ūt, ūte > out; OE hlūd > loud
OE +nd OE ġefunden > found; OE hund > hound; OE ġesund > sound (safe)
(+r) /aur/ > GA /aur/, RP /auə/ OE OE ūre > our; OE sċūr > shower; OE sūr > sour
(occ. +t) /ʌ/ OE būtan > but; OE strūtian > ME strouten > to strut


This table describes the main developments of Middle English diphthongs, starting with the Old English sound sequences that produced them (sequences of vowels and g, h or w) and ending with their Modern English equivalents. Many special cases have been ignored.

Note: V means "any vowel"; C means "any consonant"; # means "end of word".

Late Old English (Anglian) Early Middle English Late Middle English Early Modern English Modern English Example (Old and Modern English forms given)[28]
æg, ǣg /ai/ /ai/ [æi] /eː/ /ei/ dæġ > day; mæġ > may; mæġden > maiden; næġl > nail; fæġer > fair; clǣġ > clay; grǣġ > gray
eg, ēg# /ɛi/ weġ > way; pleġan > to play; reġn > rain; leġer > lair; leġde > laid; hēġ (WS hīeġ) > hay
ēgV /ei/ > /iː/ /iː/ /əi/ /ai/ ēage > ēġe > eye; lēogan > lēġan > to lie (deceive); flēoge > flēġe > fly
ig, īg, yg, ȳg /iː/ tiġel > tile; liġe > (I) lie ("recline"); hīġian > to hie; ryġe > rye; byġe > (I) buy; drȳġe > dry
æw, aw, agV /au/ /au/ /ɔː/ /ɔː/ clawu > claw; lagu > law; dragan > to draw
ǣw, ēaw, ew, eow /ɛu/ /ɛu/ /juː/ /(j)uː/ mǣw > mew; lǣwede > lewd; scrēawa > shrew; eowu > ewe
ēw, ēow /eu/ /iu/ ċēowan > to chew; hrēowan > to rue; blēow > blew; trēowþ > truth
iw, īw, yw, ȳw /iu/ hīw > hue; nīwe > new; trīewe (WS) > true; Tīwesdæġ > Tiwesdæġ > Tuesday
āw, āgV, ow, ogV, ōw, ōgV /ɔu/ /ɔu/ /ou/ > /oː/ /əu/ (British), /ou/ (American) /bou/; flogen > flown
ugV, ūgV /uː/ /uː/ /əu/ /au/ /bau/
æh, ah, ag# /auh/ /auh/ ([x] > ) /ɔː/ /ɔː/ slæht (WS sleaht) + -or > slaughter
([x] > /f/) /af/ /æf/ hlæhtor > laughter
eh /ɛih/ /ɛih/ /ei/ > /eː/ /ei/ streht > straight
ēh /eih/ > /iːh/ /iːh/ /əi/ /ai/ hēah > hēh > high; þēoh > þēh > thigh; nēh > nigh
ih, īh, yh, ȳh /iːh/ reht > riht > right; flyht > flight; līoht > līht > light
āh, āg#, oh, og# /ɔuh/ /ɔuh/ ([x] > ) /ou/ > /oː/ /əu/ (British), /ou/ (American) dāg > dāh > dough
([x] > /f/) /ɔf/ /ɒf/ (British), /ɔːf/ (American) trog > trough
āhC, ohC, ōhC /ɔuh/ /ɔuh/ /ɔː/ /ɔː/ āhte > ought; dohtor > daughter; þoht > thought; sōhte > sought
ōh#, ōg# /ouh/ > /uːh/ /uːh/ ([x] > ) /əu/ /au/ bōg > bough; plōg > plōh > plough
([x] > /f/) /ʊf/ (centralized) /ʌf/ ġenōg, ġenōh > enough; tōh > tough; ruh > rough
uh, ug#, ūh, ūg# /uːh/ (non-centralized) /ʊf/ ?

Development of Old English vowels

This table describes the main changes from Late Proto-Indo-European and Proto-Germanic up through Old English, Middle English and Modern English. It focuses on the Old English and Middle English changes leading to the modern forms. Other tables are also available to cover specific areas in more detail:

This table only describes the changes in accented syllables. Vowel changes in unaccented syllables were very different and much more extensive. In general:

  1. In Old English, long vowels were reduced to short vowels (and sometimes deleted entirely) and short vowels were very often deleted. All remaining vowels were reduced to only the vowels /u/, /a/ and /e/, and sometimes /o/. (/o/ also sometimes appears as a variant of unstressed /u/.)
  2. In Middle English, almost all unstressed vowels were reduced to /ə/; then, final /ə/ was dropped. The main exception is Old English -iġ, which becomes Modern English -y.
  3. Unstressed vowels in Modern English other than those spelled <e> are due either to compounds or to borrowed words (especially from Latin and Old French).

NOTE: The Old English words in this table are given in their Anglian form, since this is the form that underlies Modern English. However, standard Old English was based on the West Saxon dialect, and when the two dialects differ, the West Saxon form is indicated with a WS in parentheses following the Anglian form.

NOTE: In this table, abbreviations are used as follows:

1"Pre-Germanic" in this context refers to a post-PIE language that maintains PIE phonology but with morphological adjustments made as necessary to account for the Proto-Germanic form. Reconstructions are only given for solidly reconstructible Proto-Indo-European roots.

Late PIE1 Proto-Germanic1 Condition Old English Middle English Modern English Examples
  i-umlaut2   i-umlaut2   i-umlaut2
a, o, h₂e, h₃e, H̥ a   æ e /a/ /e/ /æ/; RP /ɑː/ /ɛ/ PG *paþaz > OE pæþ > "path"; PG *batizǫ̂ > OE betera > "better"; PG *taljaną > OE tellan > "to tell"
(leng.) /aː/ /ɛː/ /ei/ /iː/; /ei/; /ɛ/ PG *hwalaz > OE hwæl > "whale"; PG *matiz > OE, ME mete "food" > "meat"; PG *stadiz > OE, ME stede > "stead"
(+g) /ai/ /ɛi/ > /ai/ /ei/ /ei/ PG *dagaz > OE dæġ > "day"
(+h) /au/ /ɛu/ /ɔː/; /æf/ /(j)uː/ PG *hlahtraz > OE hlæhtor (WS hleahtor) > "laughter"; PG *slahtiz > OE sleht (WS slieht) > ME sleight "slaughter"
+n,m a,o e /a/ (occ. /o/) /e/ /æ/; occ. GA /ɔ/, RP /ɒ/ /ɛ/ PG *mannz, manniz > OE man, mon > "man", plur. men > "men"; PG *hamuraz > OE hamor > "hammer"; PG *handuz > OE hand > "hand"; PG *sange > OE past sang > "sang"; PG *lambaz > OE lamb > "lamb"; Latin candēla > OE candel > "candle"; PG *gandrǫ̂ > OE gandra > "gander"; PG *langaz > OE lang, long > "long"; PG *sandijaną > OE sendan > "send"; PG *bankiz > OE benċ > "bench"; PG *hanjō > OE henn > "hen"
(leng.) /aː/ /ɛː/ /ei/ /iː/; /ei/; /ɛ/ PG *namǫ̂ > OE nama > "name"; PG lamǫ̂ > OE lama > "lame"; PG *banǫ̂ > OE bana "slayer" > "bane"
+mf,nþ,ns ō ē /oː/ /eː/ /uː/; /ʌ/; /ʊ/ /iː/ PreG *donts, dontes > PG *tanþz, tanþiz > OE tōþ > "tooth", plur. tēþ > "teeth"; PG *gans, gansiz > OE gōs > "goose", plur. gēs > "geese"; PG *anþaraz > OE ōþer > "other"
(+CC) /o/ /e/ GA /ɔ/, RP /ɒ/; GA /ɔː/ /ɛ/ PG *samftijaz, samftô > OE sēfte, *sōfta >! OE sōfte > "soft"; PG *anstiz > OE ēst "favor" > ME "este"
+lC a æ > e /a/ /e/ /ɔː/ /ɛ/ PG *fallaną > OE fallan (WS feallan) > "to fall"; PG *fallijaną > OE fællan > fellan (WS fiellan) > "to fell"
(+ld) /ɔː/ /ɛː/ GA /ou/, RP /əu/ /iː/; /ei/; /ɛ/ PG *aldaz, aldizǫ̂ > OE ald (WS eald) > "old", ældra (WS ieldra) "older" > "elder"; PG *haldaną > OE haldan (WS healdan) > "to hold"
+rc,rg,rh æ > e e /e/ /e/ GA /ɑ/(+r), RP /ɑː/ GA /ɑ/(+r), RP /ɑː/ Latin arca > OE erc (WS earc) > "ark"
+rC (C not c,g,h) ea e /a/ /e/ GA /ɑ/(+r), RP /ɑː/ GA /ɑ/(+r), RP /ɑː/ PG *harduz > OE heard > "hard"
before a,o,u a (by analogy) æ /a/ /a/ /æ/; RP /ɑː/ /æ/; (RP) /ɑː/ Latin cattus > OE catt > "cat"
(leng.) /aː/ /aː/ /ei/ /ei/ PG *talō > OE talu > "tale"; PG *bakaną, -iþi > OE bacan > "to bake", 3rd sing. pres. indic. bæcþ "bakes"
(+g,w) /au/ /au/ /ɔː/ /ɔː/ PG plur. *dagôs > OE dagas "days" > dial. "dawes"; PG *laguz > OE lagu > "law"; PG *clawō > OE clawu > "claw"
before later a,o,u ea eo /a/ /e/ /æ/; (RP) /ɑː/ /ɛ/
(leng.) /aː/ /ɛː/ /ei/ /iː/; /ei/; /ɛ/ PG *alu(þ) > OE ealu > "ale"; PG *asiluz > OE eosol (WS esol) "donkey"
(+g,w) /au/ /ɛu/ /ɔː/ /(j)uː/ PG *awī > OE eowu > "ewe"
before hs,ht,hþ + final -iz N/A i (occ. ie) N/A /i/ N/A /ai/ PIE *nokwtis > PG *nahtiz > OE nieht > OE niht > "night"
e, h₁e, occ. i+C*e,a,o e   e N/A /e/ N/A /ɛ/ N/A PIE *nizdos > PG *nestaz > OE nest > "nest"; PG *helpaną > OE helpan > "to help"; PG *fehtaną > OE fehtan (WS feohtan) "to fight" (irreg.); PG *berkaną > OE bercan (WS beorcan) > "to bark"
(leng.) /ɛː/ N/A /iː/; /ei/; /ɛ/ N/A PG *brekaną > OE brecan > "to break"; PG *ebnaz > OE ef(e)n > "even"; OE feþer > "feather"
(+g,h) /ɛi/ > /ai/ N/A /ei/ N/A PG *wegaz > OE weġ > "way"; PG *regnaz > OE reġn > "rain"; PG *seglaz > OE seġl > "sail"
(+ld) /eː/ N/A /iː/ N/A PG *felduz > OE feld > "field"; PG *geldaną > OE ġeldan (WS ġieldan) "to pay" > "to yield"
+m i N/A /i/ N/A /ɪ/ N/A PG *remǫ̂ > OE rima > "rim"; PG *nemaną > OE niman "to take" > archaic "to nim"
(leng.) /eː/ N/A /iː/ N/A
+rC (C not c,g,h); wV; C (C not c,g) +later a,o,u eo N/A /e/ N/A /ɛ/; (+r) GA /ɑ/(+r), RP /ɑː/ N/A PG *werþaną > OE weorðan "to become"; PG *hertǭ > OE heorte > "heart"
(leng.) /ɛː/ N/A /iː/; /ei/; /ɛ/ N/A PG *etaną > OE eotan (WS etan) > "to eat"; PG *beraną > OE beoran (WS beran) > "to bear"
(+w) /ɛu/ N/A /(j)uː/ N/A
+ late final hs,ht,hþ i (occ. ie) N/A /i/ N/A /ɪ/ N/A PG *sehs > OE siex > "six"; PG *rehtaz > OE riht > "right"
i, (h₁)e+C*i, (h₁)e+C*y, (h₁)e+nC i   i i /i/ /i/ /ɪ/ /ɪ/ PG *fiską > OE fisċ > "fish"; PG *hringaz > OE hring > "ring"; PG *bidjaną > OE biddan "to pray" > "to bid"; PG *itiþi > OE 3rd sing. pres. indic. iteþ "eats"; PG *skiriþi > OE 3rd sing. pres. indic. sċirþ (WS sċierþ) "shears"; PG *stihtōjaną > OE stihtian "to establish"
(leng.) /eː/ /eː/ /iː/ /iː/ PG *wikō > OE wicu > "week"
(+g) /iː/ /iː/ /ai/ /ai/ Latin tegula > OE tiġele > "tile"; PG *brigdilaz > OE briġdel > "bridle"
(+ld,nd) /iː/ /iː/ /ai/ /ai/ PG *blindaz > OE blind > "blind" /blaind/; PG *kildaz (plur. *kildōzō) OE ċild > "child" /tʃaild/; PG *wildijaz > OE wilde > "wild" /waild/
+ mf,nþ,ns ī ī /iː/ /iː/ /ai/ /ai/ PG *fimf > OE fīf > "five"; PG *linþijō > OE līþe "gentle" > "lithe"
(+CC) /i/ /i/ /ɪ/ /ɪ/ PG *fimf tigiwiz > OE fīftiġ > "fifty"
+rC (C not c,g,h); w io > eo i /e/ /i/ /ɛ/ /ɪ/ PG *liznōjaną > OE liornian > OE leornian > "learn"; PG *a + firrijaną > OE afirran (WS afierran) "to remove" (cf. feorr "far")
(+w) /eu/ > /iu/ /iu/ /(j)uː/ /(j)uː/ PG *niwulaz > OE niowul, neowul "prostrate"; PG *spiwiz > OE spiwe "vomiting"; PG *hiwiz > OE hīw > "hue"
before a,o,u i (io, eo) N/A /i/ (/e/) N/A /ɪ/ (/ɛ/) N/A PG *milukz > OE mioluc,meolc > "milk"
(leng.) /eː/ (/ɛː/) N/A /iː/ (/iː/; /ei/; /ɛ/) N/A
(+g) /iː/ (/ɛi/ > /ai/) /iː/ /ai/ (/ei/) /ai/
u, (H), (H), (H), (H)3 u   u y /u/ /i/ /ʌ/; /ʊ/ /ɪ/ PG *sunuz > OE sunu > "son"; PG *kumaną, -iþi > OE cuman > "to come", 3rd sing. pres. indic. cymþ "comes"; PG *guldijaną > OE gyldan > "to gild"
(leng.) /oː/ /eː/ /uː/; /ʌ/; /ʊ/; (+r) GA /ɔr/, RP /ɔː/ /iː/ PreG *dhurus > PG *duruz > OE duru > "door"; PG *widuz > OE widu >! OE wudu > "wood"; PG *ubilaz > OE yfel > "evil"
(+g) /uː/ /iː/ /au/ /ai/ OE ryġe > "rye"
(+w) /uː/ /iu/ /au/ /(j)uː/
+ mf,nþ,ns ū ȳ /uː/ /iː/ /au/ /ai/ PG *munþz > OE mūþ > "mouth"; PG *kunþijaną > OE cȳþan "to make known" > ME "kithe"
(+CC) /u/ /i/ /ʌ/; /ʊ/ /ɪ/ PG *tunskaz > OE tūsc > "tusk"; PG *wunskijaną > OE wȳsċan > "wish"; PG *kunþiþō > OE cȳþþ(u) > "kith"
before non-nasal + a,e,o o (by analogy) e /o/ /e/ GA /ɔ/, RP /ɒ/ /ɛ/ PG *drupǫ̂ > OE dropa > "drop"; PG *fulką > OE folc > "folk"
(leng.) /ɔː/ /ɛː/ GA /ou/, RP /əu/; (+r) GA /ɔr/, RP /ɔː/ /iː/; /ei/; /ɛ/ PG *fulǫ̂ > OE fola > "foal"; PG *nusuz (*nusōu?) > OE nosu > "nose"; PG *hupōjaną > OE hopian > "to hope"
(+g,h,w) /ɔu/ /ɛi/ > /ai/ GA /ou/, RP /əu/; GA /ɔːf/, RP /ɒf/ /ei/ PG *duhter, duhtriz > OE dohter > "daughter", plur. dehter "daughters"; PG *trugaz > OE trog > "trough"; PG *bugǫ̂ > OE boga > "bow" /bou/
(+ld,rd) /ɔː/ /ɛː/ GA /ou/, RP /əu/; (+r) GA /ɔr/, RP /ɔː/ /iː/; /ei/; /ɛ/ PG *guldaz > OE gold > "gold"; PG *burdą > OE bord > "board"
ē(H), eh₁ ǣ > ā   ē ē /eː/ /eː/ /iː/ /iː/ PG *slǣpaną > OE slēpan (WS slǣpan) > "to sleep", Latin strāta > OE strēt (WS strǣt) > "street"; PG *dǣdiz > OE dēd (WS dǣd) > "deed"; Latin cāseus > OE ċēse (WS ċīese) > "cheese"
(+CC) /e/ /e/ /ɛ/ /ɛ/
(+g,h) /iː/ /iː/ /ai/ /ai/ PG *nǣhaz, nǣhistaz > OE nēh (WS nēah) "near" > "nigh", superl. nēhst (WS nīehst) "nearest" > "next"
+n,m ō ē /oː/ /eː/ /uː/ /iː/ PG *mǣnǫ̂ > OE mōna > "moon"; PG *kwǣniz > OE kwēn > "queen"
+w; ga,go,gu ā ǣ /ɔː/ /ɛː/ GA /ou/, RP /əu/ /iː/; /ei/; /ɛ/
(+g) /ɔu/ /ɛi/ > /ai/ GA /ou/, RP /əu/ /ei/ PG *mǣgôz > OE māgas "relatives"
(+w) /ɔu/ /ɛu/ GA /ou/, RP /əu/ /(j)uː/ PG *knǣwaną, -iþi > OE cnāwan > "to know", 3rd sing. pres. indic. cnǣwþ "knows"
ēi, iz, etc.4 ē   ē ē /eː/ /eː/ /iː/ /iː/ PG *hēr > OE hēr > "here"; PIE *mizdhā > PG *mēdō > OE mēd "reward"
(+g,h) /iː/ /iː/ /ai/ /ai/ OE past hēht "called" > "hight"
(+w) /eu/ > /iu/ /eu/ > /iu/ /(j)uː/ /(j)uː/
ā, ō, aH, oH, eh₂, eh₃; an+K, on+K, h₂en+K, h₃en+K ō; ą̄+h   ō ē /oː/ /eː/ /uː/; /ʌ/; /ʊ/ /iː/ PG *fōtz, fōtiz > OE fōt > "foot", plur. fēt > "feet"
(+CC) /o/ /e/ GA /ɔ/, RP /ɒ/; GA /ɔː/ /ɛ/ PG *kōpi-dǣþ > OE cēpte > "kept"; PG *mōti-dǣþ > OE mētte > "met"
(+g,h) /ɔu/; /uː/ /iː/ GA /ou/, RP /əu/; /au/; /ʌf/ /ai/ PG *swōganą > OE swōgan "to sound" > ME /sɔuə/ > "sough" /sou/; PG *bōgaz > OE bōg > ME /buːh/ > "bough" /bau/; PG *tōhaz > OE tōh > ME /tuːh/ > "tough" /tʌf/; PG past *sōh-dǣþ > OE sōhte > ME /sɔuhtə/ > "sought"
(+w) /ɔu/ /eu/ > /iu/ GA /ou/, RP /əu/ /(j)uː/ PG *grōwaną > OE grōwan > "grow"
(h₁)ei, ī, iH; (h₁)en+K, in+K ī; į̄+h   ī ī /iː/ /iː/ /ai/ /ai/ PG *wībą > OE wīf > "wife"; PG *līhiþi > 3rd sing. pres. indic. līþ (WS līehþ) "lends"; PIE *lengwhtos > PG *lį̄htaz > OE līht (WS lēoht) > "light" (in weight)
(+CC) /i/ /i/ /ɪ/ /ɪ/
(+g,h) /iː/ /iː/ /ai/ /ai/ PG *hīgōjaną > OE hīgian > "hie"
(+w) /iu/ /iu/ /(j)uː/ /(j)uː/ PG *Tīwaz > OE Tīw (name of a god) + -es "'s" + dæġ "day" > "Tuesday"
ū, uH; n̥+K, un+K ū; ų̄+h   ū ȳ /uː/ /iː/ /au/ /ai/ PG *mūs, mūsiz > OE mūs "mouse", plur. mȳs > "mice"; PG *hūdijaną > OE hȳdan > "to hide"
(+CC) /u/ /i/ /ʌ/; /ʊ/ /ɪ/ PG *rūstaz > OE rūst > "rust"; PIE *pn̥kʷstis > PG *fų̄hstiz > OE fȳst > "fist"
(+g,h) /uː/ /iː/ /au/; /ʌf/ /ai/ PG *būganą > OE būgan "to bend" > "bow"; PG *rūhaz > OE rūh > "rough" /rʌf/; PG *drūgijaz > OE drȳge > "dry"
(+w) /uː/ /iu/ /au/ /(j)uː/ OE trūwian "to trust" > archaic "trow" /trau/
ai, oi, h₂ei, h₃ei ai   ā ǣ /ɔː/ /ɛː/ GA /ou/, RP /əu/; (+r) GA /ɔr/, RP /ɔː/ /iː/; /ei/; /ɛ/ PG *stainaz > OE stān > "stone"; PreG perfect *roidhe > PG past *raide > OE rād > "rode"; PreG *oyerā > PG *airō > OE ār > "oar"; PIE *ayes > PG *aiz > OE ār "bronze" > "ore"; PG *hwaitiją > OE hwǣte > "wheat"
(+CC) /a/ /a/ /æ/; RP /ɑː/ /æ/; RP /ɑː/ PG *faittiz > OE fǣtt > "fat"
(+g,h) /ɔu/ /ɛi/ > /ai/ GA /ou/, RP /əu/ /ei/ PG *aiganą > OE āgan > "owe"; PG *daigaz > OE dāg, dāh > "dough"
(+w) /ɔu/ /ɛu/ GA /ou/, RP /əu/ /(j)uː/ PG *maiwiz > OE mǣw > "mew"
au, ou, h₂eu, h₃eu au   ēa ē /ɛː/ /eː/ /iː/; /ei/; /ɛ/ /iː/ PG *auzǭ > OE ēare > "ear"; PG *hauzijaną > OE hēran (WS hīeran) > "to hear"
(+w) /ɛu/ /eu/ > /iu/ /(j)uː/ /(j)uː/ PG *skrawwǫ̂ > OE sċrēawa > ME "shrewe" > "shrew"
+c,g,h; rc,rg,rh;lc,lg,lh ē ē /eː/ /eː/ /iː/ /iː/ PG *auke(?), *aukijaną > OE ēc, ēċan (WS ēac, īeċan) "also, to increase" > ME "eke, eche" > "eke" (archaic), "to eke"
(+g,h) /iː/ /iː/ /ai/ /ai/ PG *augǭ > OE ēġe (WS ēage) > "eye"; PG *hauhaz, hauhistaz > OE hēh (WS hēah) > "high", superl. hēhst (WS hīehst) "highest"; PIE *leuktos > PG *leuhtaz > OE lēht (WS lēoht) > "light" (brightness)
(h₁)eu eu   ēo N/A /eː/ N/A /iː/ N/A PG *deupaz > OE dēop > "deep"; PG *beudaną > OE bēodan "to command"
(+w) /eu/ > /iu/ N/A /(j)uː/ N/A PG *hrewwaną > OE hrēowan > "to rue"
+c,g,h; rc,rg,rh; lc,lg,lh ē N/A /eː/ N/A /iː/ N/A PG *reukaną > OE rēcan (WS rēocan) > "to reek"
(+g,h) /iː/ N/A /ai/ N/A PG *fleugǭ > OE flēge (WS flēoge) > "fly"; PG *leuganą > OE lēgan (WS lēogan) > "to lie"
(h₁)eu+C*i, (h₁)eu+C*y iu   N/A īo > ēo N/A /eː/ N/A /iː/ PIE *newios > PG *niujaz > OE nīwe > "new"; PG *biudiþi > 3rd sing. pres. indic. bīott (WS bīett) "commands"
(+w) N/A /eu/ > /iu/ N/A /(j)uː/ PG *triwwiz > *triwwijaz > OE trīowe, trēowe > ME "trewe" > "true"
+c,g,h; rc,rg,rh; lc,lg,lh N/A ī N/A /iː/ /ai/ /ai/ PIE *leuktionom > PG *liuhtijaną > OE līhtan (WS līehtan) "to light"

1A + separates the sounds that produced the Proto-Germanic vowels in question from the sounds that formed the conditioning environment. The notation C* means a sequence of zero or more consonants.

2I-umlaut refers to a sound change that took place around 500 AD with pervasive effects on English vowels. Specifically, vowels were fronted or raised whenever an /i/ or /j/ followed in the next syllable. Nearly every vowel was affected. Affected vocabulary is shown in a different color.

3PIE and H became Proto-Germanic un; similarly for , and . K refers to either of the PIE sounds or k, which fell together in Proto-Germanic and the other Centum languages; or to any of the nine PIE velars when followed directly by a voiceless consonant (especially t). H refers to any laryngeal sound. The ogonek (e.g. ą, ǭ) indicates a nasal vowel. Long vowels are noted with a macron (e.g. ē, ō). Extralong vowels are noted with a circumflex (e.g. ô).

4The origins of Proto-Germanic ē are somewhat in dispute.

See also


  1. 1 2 Campbell 1959, pp. 52–53.
  2. Campbell 1959, pp. 60–62.
  3. Campbell 1959, pp. 50–51.
  4. Campbell 1959, pp. 54–60.
  5. Campbell 1959, p. 53.
  6. Cercignani 1983.
  7. Campbell 1959, pp. 64–71.
  8. Campbell 1959.
  9. Mitchell & Robinson 2001.
  10. Lass 1994.
  11. Campbell 1959, pp. 186–187.
  12. Campbell 1959, pp. 104–105.
  13. Campbell 1959, pp. 98–104.
  14. Campbell 1959, pp. 85–93.
  15. Campbell 1959, pp. 155–156.
  16. Campbell 1959, pp. 143–144.
  17. Cercignani 1981.
  18. Wells 1982, pp. 192–94, 337, 357, 384–85, 498..
  19. Dobson 1968, p. 720.
  20. Trudgill 2002, p. 71.
  21. Wells 1982, pp. 245–47.
  22. Wells 1982, pp. 339–40, 419.
  23. Trudgill 2002, pp. 28-30.
  24. Trudgill 2002, pp. 77–78.
  25. Trudgill 2002, pp. 63–66.
  26. Dobson, E.J. (1957), English Pronunciation 1500–1700, London: Oxford University Press, p. 558
  27. Dobson, E.J. (1957), English Pronunciation 1500–1700, London: Oxford University Press, pp. 677–678
  28. Many examples from Fernand Mossé (1968), A Handbook of Middle English, tr. James Walker, Baltimore: Johns Hopkins Press, pp. 27–29.


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