Colloquial Welsh morphology

The morphology of the Welsh language has many characteristics likely to be 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 is no case inflection in Modern Welsh.

Modern Welsh can be written in two varieties — Colloquial or Literary. The grammar described on this page is for Colloquial Welsh, which is used for speech and informal writing. Literary Welsh is closer to the form of Welsh used in the William Morgan's 1588 translation of the Bible and can be seen in formal writing.

Initial consonant mutation is a phenomenon common to all Insular Celtic languages, although 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 when preceded by certain words (e.g. i, yn, and a), or because of some other grammatical context (such as when the grammatical object directly follows the grammatical subject). Welsh has three mutations: the soft mutation, the nasal mutation, and the aspirate mutation. These are also represented in writing:

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