Appendix:Old Irish class A I present verbs

Old Irish class A I verbs (Strachan's B1, McCone's W1) are derived from Proto-Celtic verbs ending in, which are derived from Proto-Indo-European verbs ending in and correspond to the Latin first conjugation, Ancient Greek verbs in , and Germanic class 2 weak verbs in. The final consonant of the stem is nonpalatalized throughout, meaning that any consonant-initial endings also start with a nonpalatalized consonant.

See Category:Old Irish class A I present verbs for a list of verbs belonging to this class.

Nondeponent endings
A sample verb for this class is. The endings are as follows:

The letter ⟨t⟩ stands for in all third-person plural and passive plural endings.

See Appendix:Old Irish delenition for the change of ending-initial ⟨th⟩ to ⟨t⟩ after certain consonants.

In some cases, a vowel is inserted (historically speaking, fails to be deleted) before consonant-initial endings. This vowel is found especially after stems ending in a consonant cluster that cannot be followed by a third consonant, and after stems ending in one of the dental obstruents, but it also sometimes found in other cases. When this vowel appears, the initial consonant of the ending is in most cases palatalized. In addition, a consonant cluster that cannot end a word is broken up by an epenthetic vowel in the second-person singular imperative. An example is :

Deponent endings
A sample verb for this class is. The endings are as follows:

Here again, certain consonant clusters take a vowel before consonant-initial endings, e.g. :