Literary Welsh morphology

The morphology of the Welsh language shows many characteristics perhaps unfamiliar to speakers of English or continental European languages like French or German, but has much in common with the other modern Insular Celtic languages: Irish, Scottish Gaelic, Manx, Cornish, and Breton. Welsh is a moderately inflected language. Verbs inflect for person, tense and mood with affirmative, interrogative and negative conjugations of some verbs. There are few case inflections in Literary Welsh, being confined to certain pronouns.

Modern Welsh can be written in two varieties – Colloquial Welsh or Literary Welsh. The grammar described on this page is for Literary Welsh.

Initial consonant mutation is a phenomenon common to all Insular Celtic languages (there is no evidence of it in the ancient Continental Celtic languages of the early first millennium). The first consonant of a word in Welsh may change depending on grammatical context (such as when the grammatical object directly follows the grammatical subject), when preceded by certain words, e.g. i, yn, and a or when the normal word order of a sentence is changed, e.g. Y mae tŷ gennyf, Y mae gennyf dŷ "I have a house".

Welsh has three mutations: the soft mutation, the nasal mutation, and the aspirate mutation. These are also represented in writing:

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