3. New Diphthongs

OE diphthongs turned into monophthongs:

OE Diphth.	ME Sounds	OE	ME
ĭě/īē 	i	līehtan	lighten (lighten)
ĕŏ/ēō 	e	heorte	herte (heart)
ĕă/ēā 	æ	ēast	eest (east)

New diphthongs appeared due to vocalisation of [j], [γ] and [w]. These consonants turned into vowels ([i], [u] and [u] respectively) and became the glides of the new diphthongs:

i-glides	OE	ME	u-glides	OE	ME
[ei]	weζ[j]	wey[i] (way)	[iu]	-	-
[ai]	mæζ[j]	may[i] (may)	[au]	laζ[γ]u	law[u]e [‘lauə] (low)
[oi] (in French loan-words)		boy, toy	[ou]	cnāw[w]an	know[u]en [‘knouən] (know)

2. English consonants proved to be more stable than vowels. Nevertheless, new sets of consonants started to appear.

1. Sibilants and Affricates

Sibilants – a type of fricatives, narrower and sharper than all other fricatives ([f, v, , ð, h]) – [s, z, ∫, ζ].

Affricates – sounds consisting of a plosive immediately followed by a fricative – [t∫, dζ].

In OE there were only 2 sibilants – [s, z]. [∫] appeared in ME period.

Affricates [t∫, dζ] appeared both in ME and in NE.

New consonants developed from palatal plosives [k’], [g’] and the cluster [sk’]:

OE Sounds	ME Sounds	In Writing	OE	ME
[k’] 	[t∫]	tch, ch	cild [k’il’d]	child [t∫ild]
[g’] 	[dζ]	g, dg	ecge [‘egg’ə]	edge [‘edζə]
[sk’] 	[∫]	sh, ssh, sch	fisc [fisk’]	fish [fi∫]