bone up vs mug up

bone up and mug up both are verbs.

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

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

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

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