Middle English

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

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