Model: steigen
Auxiliary: sein
Other forms: heraufsteigen/nicht 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
Perfekt
Plusquamperfekt
Futur II
Futur I