Strong Verb, Class 7,
Several vowel gradations in this class (also known as reduplicating verbs); infinitive and past participle stem vowels ordinarily the same (except for contractions, e.g., onfon); first and second preterit stem vowels (with e or eo / io) usually the same.
Examples:
hatan, het / heht, heton, haten
lætan, let, leton, (ge)læten
ondrædan, ondred, ondredon, ondræden
onfon, onfeng, onfengon, onfangen
healdan, heold / hiold, heoldon, (ge)healden
wealdan, weold, weoldon, (ge)wealden
gangan / gongan, geong / giong / gang, geongon, (ge)gangen
weallan, weol(l) / weall, weollon, (ge)wellen