Appendix:Old Irish t preterite verbs

The Old Irish t preterite originated in Proto-Celtic in forms where the preterite suffix -s- came between a root-final consonant and the third-person singular ending -t. The s disappeared by phonological rule in this environment, and the remaining -t was reinterpreted as a tense-marking suffix and spread to the rest of the paradigm. The t preterite is found on strong verbs whose root ends in one of the consonants r, l, m, and g (though not on all such strong verbs).

The t endings are generally added directly to the verb root, but takes the reduplicated form  (< ).

The t preterite is found in a few forms in Brythonic as well, e.g.,.

As with the s preterite, the passive forms are derived from a verbal adjective with a suffix starting with t.

See Category:Old Irish t preterite verbs for a list of verbs belonging to this class.

Nondeponent endings
A sample verb for this class is, which ends in a broad consonant. The endings are as follows: