Irregular verbs have no rules for conjugation. These can only be learnt
in context - sorry!
They all have a base form.
e.g. to run
A gerund (ing) form where ing is added to the end of the verb.
e.g. running
An -s form where s is added to the end of the verb.
e.g. runs
A past tense form which must be learnt.
e.g. ran
A past participle form which must be learnt.
e.g. run