There are two categories of verbs in Irish, and you need to know which category a verb belongs to before you can conjugate it. Fortunately, it is very easy to remember the categories. You also need to be able to tell if the verb ends in a broad or slender consonant. This means that you need to know four sets of endings, one for each of the following cases: Or does it? Some people memorise it that way. Others memorise only two sets of endings, one set forType 1 verbs, one for Type 2 verbs, and then apply the "caol le caol agus leathan le leathan" rule. I myself find it easiest to memorise one set of endings, plus a small set of "middles", and then apply the "caol le caol agus leathan le leathan" rule. Whichever way you do it, you will get the same result. But if you find my system confusing, by all means ignore this and follow the method described by your book or teacher.

Here are the tables I used to learn how to conjugate verbs in Irish. The stem of a regular verb is the imperative singular, the form you use to give a command. The format used in these summary tables is shown below.

-------------------------------------------
|     ending for      |    ending for     |
| 1st person singular | 1st person plural |
-------------------------------------------
|     ending for      |    ending for     |
| 2nd person singular | 2nd person plural |
-------------------------------------------
|     ending for      |    ending for     |
| 3rd person singular | 3rd person plural |
-------------------------------------------
               | ending for |
               | autonomous |
	       --------------
Endings in italics indicate synthetic forms, which express action + person + number in one word; they are not followed by a personal pronoun. Endings in bold indicate analytic forms, which must be followed by a personal pronoun.
Present (Habitual)      ---------------
Type 1: stem + ...      |  im  | imid |
Type 2: stem + í + ...  ---------------
                        |    ann      |
                        |             |
                        ---------------
                            | tar |
                            -------

Past                               ---------------
Lenite, add d' before vowel or f,  |      | amar |
except autonomous form.            |      --------
Type 1: stem + ...                 |    ...      |
Type 2: stem + í + ...             |             |        
                                   ---------------
                                      | adh |
                                      -------

Future                      ---------------
Type 1: stem + f + ...      |      | imid |
Type 2: stem + {ó|eo} + ... |      --------
                            |    idh      |
                            |             |
                            ---------------
                                | far |
                                -------

Imperfect (Past Habitual)          ---------------
Lenite, add d' before vowel or f.  | inn  | imis |
Type 1: stem + ...                 ---------------
Type 2: stem + í + ...             |    | adh  |
                                   --------------
                                   | adh  | idís |
                                   ---------------
                                       |   |
                                       -------

Conditional                        ---------------
Lenite, add d' before vowel or f.  | inn  | imis |
Type 1: stem + f +...              ---------------
Type 2: stem + {ó|eo} + ...        |    | adh  |
                                   --------------
                                   | adh  | idís |
                                   ---------------
                                       |   |
                                       -------
HINT: Most of the endings are the same as in the Imperfect (Past Habitual) .
Imperative               ---------------
Type 1: stem + ...       |  im  | imis |
Type 2: stem + í + ...   ---------------
                         | ...  | igí  |
                         ---------------
                         | adh  | idís |
                         ---------------
                             | tar |
                             -------

Present Subjunctive      ---------------
Type 1: stem + ...       |      | imid |
Type 2: stem + í + ...   |      --------
                         | a or e, ... |
                         ---------------
                             | tar |
                             -------

Past Subjunctive
Same endings as past habitual, but don't lenite. 

Direct relative
Except for combined forms:
Add broad s to present habitual and future
idh -> (e)as

Verbal noun (general guidelines) 
Type 1: stem + adh
Type 2: stem + ú 
Verbs ending in -(e)áil: stem (no ending)
Verbs ending in slender l, n, r: stem + t

Verbal adjective
Type 1: stem + ta or te
Except: tha or the after b, c, f, g, m, p, r
Except: Drop bh or mh and add fa

Type 2: stem + ithe
Except: te after l, n, r (don't syncopate)
General Rules (for all tenses)
  • ía -> ío
  • Drop a after á,ó,ú
  • after slender consonant, ó -> eo
  • t(h) + t -> t
  • When an ending begins with a consonant, pad it with a vowel after the consonant, if needed to satisfy the "caol le caol agus leathan le leathan" rule.
Rules For Type I Verbs
  • -áigh, -óigh, -úigh, -eoigh, -uaigh, drop (i)gh and use broad f and slender t in verb endings.
  • -éigh, drop (i)gh and use slender f and slender t in verb endings.
  • -igh alone or after short vowel, drop gh, i -> í (except before t), and use slender f and slender t in verb endings... except for the verb "faigh".
  • áil -> ál unless ending begins with t
Rules For Type II Verbs
  • If ending has an initial vowel, drop last syllable:
  • drop (a)igh
  • drop (a)i before final l, n, r, s
Now that you've masterd the regular verbs, why not try the irregular ones?