Model: steigen
Auxiliary: sein
Other forms: heraufsteigen/sich heraufsteigen
Irregular conjugation for ther verbs "steigen", "schweigen" and their compounds: there is a a vowel change in the stem of Present tense ("ich steige") and the stem of Preterite ("ich stieg") and the stem of Past Participle ("gestiegen").
Präsens
Präteritum
Futur I
Perfekt
Plusquamperfekt
Futur II