mug up vs bone up

mug up and bone up both are verbs.

Word	Noun	Adjective	Verb	Adverb
mug up	No	No	Yes	No
bone up	No	No	Yes	No

As verbs, mug up and bone up are synonyms defined as:

Other synonyms of mug up include bone, cram, drum, get up, grind away, swot, swot up.

mug up (verb)	bone up (verb)
study intensively, as before an exam	study intensively, as before an exam