Sound changes which affect segments can either be conditioned, meaning that they only occur in specific phonetic environments, or unconditioned, meaning that they can affect all occurrences of a particular sound. One regularly occurring type of conditioned change is assimilation, a process through which one sound becomes more like another in its environment. Assimilation can be complete, in that the sounds involved in the process become identical (as in Latin septem Italian sette), or it can be partial, so that instead they come to share certain features. For example, texts indicate that medial [v] in OE efen/efn ‘even’ was sometimes replaced by nasal [m] through assimilation to final nasal [n], resulting in spellings such as emn. A more recent example of partial assimilation can be heard in the pronunciation [hambæg] (handbag), which results from the replacement of [n] by bilabial nasal [m], because of conditioning bilabial [b]. In all of these examples, assimilation is considered anticipatory or regressive, in that the affected sound precedes the conditioning one. In peseverative or progressive assimilation, however, that order is reversed, as can be seen in the derivation of OE wull ‘wool’ from ancestral Germanic *wulno.2 Finally, assimilation can also be distant, in that the conditioning and affected sounds are separated by intervening segments. In Chapter 3, we will look at a particular instance of such assimilation, namely i-mutation, which affected certain nouns in the Germanic ancestor of English. Words such as feet and goose are descended from forms which marked their respective plurals with a final inflectional –i, as in *fo¯t/*fo¯ti (‘foot/feet’) and *go¯s/*go¯si (‘goose/geese’). Anticipatory but distant assimilation with final –i caused fronting of the stem vowel and by the late OE period, this long o¯ [o:] had been replaced by long front [e:]. Final conditioning –i had also been obliterated, hence OE spellings such as fe¯t and ge¯s. A much later shift from [e:] to [i:] (see Chapter 5) resulted in our modern pronunciations of these words.