As an irregular verb, however, its past tense form is characterized by ablauting ('any vowel change that alternates') in which /e/ -> /o/ (/brek/ -> /brok/) and its past participle form is characterized by both ablauting and /(e)n/ addition.
the process of vowel turning into its ablaut variant
Silbentrennung
the proc·ess of vow·el turn·ing in·to its ab·laut va·ri·ant