part of the colloquial language and is used by native speakers. h-prothesis h-prothesis is a phenomenon in Welsh in which a vowel-initial word becomes h-initial. It occurs after the possessive pronouns 'her', 'our', and 'their': 'age', 'her age' (c.f. 'his age'). It also occurs with 'twenty' after 'on' in the traditional counting system: 'twenty-one', literally "one on twenty". Irish Irish has two consonant mutations: lenition ( [ˈʃeː.vʲuː]) and eclipsis ( [ˈʊ.ɾˠuː]). Lenition Lenition () is indicated by an h following the consonant in question or, in some older typefaces and texts, by a dot (◌̇) above the letter that has undergone lenition. The effects of lenition are as follows: A stop becomes a fricative. Voicing is retained, as is place of articulation except for the coronals. → → → → → → → , → → → → → becomes or ; becomes . and become , but , , , , , and do not mutate. and are deleted. Eclipsis The following tables show how eclipsis affects the start of words. Eclipsis is symbolised in the orthography by adding a letter, or occasionally two letters, to the start of the word. If the word is to be capitalised, the original first letter is capitalised, not the letter or letters added for eclipsis. An example is the "F" in Ireland's national anthem, Amhrán na bhFiann. Russian In Russian, consonant mutation and alternations are a very common phenomenon during word formation, conjugation and in comparative adjectives. The most common classes of mutations are the alternation between velar and postalveolar consonants: → → → , as in "quiet" and "quieter" Gain or loss of palatalization: "tsar" and "of the tsar" (adjective) Other common mutations are: → (or less frequently щ ), → → , → , → → : плеск → плещет "splash" / "(he) splashes", → : свистеть → свищу "to whistle" / "I whistle" Hebrew Modern Hebrew shows a limited set of mutation alternations, involving spirantization only. The consonants affected may be stem-initial, stem-medial, or stem-final. However, in Modern Hebrew, stop and fricative variants of , and are sometimes distinct phonemes: For a more in depth discussion of this phenomenon, see Begadkefat. Japanese Rendaku, meaning "sequential voicing," is a mutation of the initial consonant of a non-initial component in a Japanese compound word: nigiri + sushi → nigirizushi ("grip (with the hand)" + "sushi" → "hand-shaped sushi") nigori + sake