Irregular verbs in the past tense

In German, many verbs have irregular forms in the past tense, also known as Präteritum or Imperfekt. These irregularities can involve vowel changes, consonant changes, or a combination of both. For example, the verb "sein" (to be) has an irregular form of "war" in the past tense. A similar English tense to Präteritum is the simple past tense.