Cleave (split)

'To cleave (meaning (1))' is an irregular verb. Its forms are given here:

Base form	past tense	-ed participle	Remarks
cleave (meaning (1))	cleft or clove	cleft or cloven	The 'regular variant' of Class 3 part. Adj: e.g. cleft palate; cloven hoof. See also cleft - cloven. Beware the distinction between two cleaves

This is one of the "the 250 or so irregular verbs" listed in Quirk 1985. The list "contains most of the irregular verbs in present-day English ... but is not meant to be exhaustive, particularly with regard to derivative verbs." AWE has copied most of the entries in that list. The verb 'to cleave (meaning (1))' belongs to Quirk's Class 3 A