There are some types of irregular verbs, except:

Verbs in which all the three forms are identical (e.g. cut – cut – cut)

Verbs in which two of the three forms are the same (e.g. sit – sat – sat)

Verbs in which all three forms are different (e.g. drink – drank – drunk)

Verbs can be both regular and irregular. (e.g. Dream – dreamt – dreamt / Dream – dreamed – dreamed)

Verbs in which different vowels replace the radical vowel in the imperfect. (e.g. at drikke, 'to drink,'—i. i. drak, p. p. drukket)