Vowels in the unstressed position

All vowels in the unstressed position changed and became [ə] or [i] unstressed. This phonetic change had a far-reaching effect upon the system of the grammatical endings of the English words, which now due to the process of reduction became homonymous. For example:

- forms of strong verbs

Vowels under stress

In the ME period a great change affected the entire system of vowel phonemes.

OE had both short and long vowel phonemes, and each of these could occur in any phonetic environment, i.e. they were absolutely independent phonemic units.

As a result of important changes coming into the vowel system in the 10^th – 12^th centuries, the ME vowel system was basically different. While in OE quantity (i.e. length/shortness) was a distinctive phonemic feature, in ME (by the 13^th century) quantity of vowels becomes dependent on their environment – to be exact, on what follows. In some phonetic environments only short vowels can appear, while in other phonetic environments only long vowels can appear.

Changes of monophthongs

Three long monophthongs underwent changes in Middle English:

Table 7.2

Long monophthongs

Periods Sounds	OE	ME	NE
ā > ō	stān bāt	stōn bōt	stone boat
æ: > ē	slæ:pan	slēpen	sleep
y: > ī	fy:r	fīr	fire

The rest of the monophthongs retained their original quality, for example:

OE ME

ē < ee tēþēþ teeth

ō < oo tōþōþ tooth

ū < ou ūt out

ī < ii tīma time

Out of seven principal OE short monophthongs: a, e, o, i, u, æ, y – two changed their quality in ME:

[æ] > [a] pæt that

wæs was

[y] > [i] fyrst first

but the rest of the monophthongs remained unchanged, e. g:

tellan tellen

hors hors

sin¥an singen

putan putten

Changes of diphthongs

One of the most important sound changes of the Early ME period was the loss of

the OE diphthongs and the growth of new diphthongs. OE possessed a well developed

system of diphthongs. Towards the end of the OE period all the diphthongs were contracted (i.e. became monophthongs).

Table 7.3

Table 2.

Development of Old English diphthongs in Early Middle English

Periods Sounds	OE	ME
ēo > ee	dēop	deep
ēa > ee	brēad	bread
eo > e	seofon	seven
ea > a	eald	ald

As a result of these changes the vowel system lost two sets of diphthongs, long and short. In the meantime a new set of diphthongs developed from some sequences of vowels and consonants due to the vocalization of OE [j] and [γ], (i.e. to their change into vowels).

Table 7.4