E.g. audï/re = audï plus s = audïsNöta bene: there is an extra "u" in the 3rd person pres plural. Don't question it, just memorize it.
Remember, the -ï becomes short before other vowels and "t".
4th Conjugation - Present Indicative Activeaudiö - audïmus3rd Conjugation -iö - Present Indicative Active
audïs - audïtis
audit - audiuntcapiö - capimus
capis - capitis
capit - capiunt
A word from the philologists on the "io" verbs:
Verbs of the Third Conjugation in "iö" have certain forms of the present stem like the fourth conjugation. They lose the i of the stem before a consonant and also before i, ï, and e (except in the future, the participle, the gerund, and the gerundive).[This is a practical working rule. The actual explanation of the forms of such verbs is not fully understood.] [Allen and Greenough Latin Grammar, 188].
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