Dependent and independent verb forms

In the Goidelic languages, dependent and independent verb forms are distinct verb forms; each tense of each verb exists in both forms. Verbs are often preceded by a particle which marks negation, or a question, or has some other force. The dependent verb forms are used after a particle, while independent forms are used when the verb is not subject to a particle. For example, in Irish, the past tense of the verb feic ("to see") has two forms: the independent form chonaic and the dependent form faca. The independent form is used when no particle precedes the verb, as in Chonaic mé Seán ("I saw John"). The dependent form is used when a particle such as ní ("not") precedes the verb, as in Ní fhaca mé Seán ("I did not see John").

The distinction between dependent and independent forms originates with two distinct but related phenomena in Old Irish: the contrast between absolute and conjunct verb endings, and the contrast between prototonic and deuterotonic forms.

Old Irish verbs that have no prefixes, called "simple verbs", have two sets of endings, absolute and conjunct. The conjunct endings are used after a variety of grammatical particles, including among others the negative particle ní ("not"), the interrogative particle in, and prepositions combined with the relative pronoun (e.g. lasa "with which"). Where no such "conjunct particle" is present, the absolute endings are used. For example, "he calls" is gairid (absolute), while "he does not call" is ní·gair and "with which he calls" is lasa·ngair (both conjunct). (An interpunct "·", hyphen "-", or colon ":" is usually used to indicate conjunct forms in pedagogical and analytical works on Old Irish. Actual manuscripts do not use such punctuation marks.) When a particle is present, stress falls on the first syllable of the verb itself, i.e. the syllable after the "·" mark.

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