DEUTSCHE VERBEN 2. IRREGULAR VERBS
SEIN = TO BE SEIN is probably the most irregular verb there is in German. All of its forms just have to be memorized. Unfortunately, it is the verb you use the most. Its annoying, but remember that TO BE in English is not much better! I am, you are, he/she/it is...
SEIN = TO BE ich binwir sind du bistihr seid er, sie, es istsie, Sie sind
HABEN = TO HAVE Haben is not too irregular. The only irregularity is that, in the du- and er/sie/es-forms, there is no –b- in the stem.
HABEN = TO HAVE ich habewir haben du hastihr habt er, sie, es hatsie, Sie haben