This planned new article will describe the verb in Gothic parallel to the article West Germanic strong verb. It is subsidiary to the article Germanic verb. In the Germanic languages, strong verbs are those which mark their past tenses by means of ablaut. ... The Germanic language family is one of the language groups which resulted from the breakup of Proto-Indo-European. ...

Indo-European

The Indo-European vowel-alternations could be as follows:

• ei — oi — i
• eu — ou — u
• e — o — (zero)

These are all the same. An alternation between e - o - — (zero)

• o — ō — a

This one is:

• eh₃ - oh₃ - h₃

Where h₃ is a laryngeal. The important point is that all these classes are one and the same from an I-E point of view. The laryngeals were three consonant sounds that appear in most current reconstructions of the Proto-Indo-European language. ...

Germanic

In Germanic, these became the following classes:

• ī — ai — i
• iu — au — u/o
• e/i — a — u/o
• a — ō — a

In the last class there was also a lengthened grade with ē

In Gothic we find these forms:

• dreiban (ei = ī) — draif (3sing) — dribun (3pl) — dribans (past participle)
• biudan — bauþ — budun — budans
• hilpan (from *helpan) — halp — hulpun — hulpans
• qiman (from *qeman) — qam — qemun (e = ē) — qumans
• faran — for (o = ō) — forun (o = ō) — farans

In addition, we find a class of reduplicating verbs, with or without vowel alteration:

• haitan — haihait (=hehait) — haihaitun (=hehaitun) — haitans
• tekan — taitok — taitokun — tekans