Second aorist active verbs function exactly like first aorist active indicative verbs, but they are formed differently. As we noted previously, first aorist verbs may be likened to "weak" verbs in English, while second aorist verbs are like "strong" verbs. How so?

Compare the present tense and aorist tense forms of the following verbs:

Observe how under the "weak" pattern, the aorist verb forms as one might expect. The epsilon augment, lexal (present tense stem), aspect morph, and suffix slots are filled appropriately to form a first aorist verb. But under the "strong" pattern, although we can identify the epsilon augment, the connecting vowel o, and a secondary active suffix (-men), the lexal seems to have changed. Also, there is no aspect morph such as the sa in first aorist verbs.

It is a unique lexal (a lexal that varies from that of the lexical form) which will often serve as a clue leading to the identification of a second aorist verb. This unique lexal will be particularly important in differentiating between imperfect and second aorist verbs.

Second aorist active indicative verbs are easy to learn because they are formed in almost the same way as imperfects. Like the imperfect, the second aorist has an epsilon augment, and secondary active endings joined to its verb stem with connecting vowels. The difference between the formation of the imperfect and the formation of the second aorist is that the imperfect is built on the present tense stem, while the second aorist has it own unique stem.

Observe the comparison of the following morph slot analysis of second aorist and imperfect verbs.

For more information on second aorist stems, cf. Black, Learn, §53.

The second aorist active indicative endings are identical to those of the imperfect active indicative: 

Notice that the 1 sg and 3 pl suffixes are identical, so that the person and number of this form has to be determined by observing the co-text.