break in vs commence

break in and commence both are verbs.

Word	Noun	Adjective	Verb	Adverb
break in	No	No	Yes	No
commence	No	No	Yes	No

As verbs, commence is a hypernym of break in; that is, commence is a word with a broader meaning than break in:

Other hypernyms of break in include begin, get, get down, set about, set out, start, start out.

break in (verb)	commence (verb)
make submissive, obedient, or useful	take the first step or steps in carrying out an action
break so as to fall inward	set in motion, cause to start
start in a certain activity, enterprise, or role	get off the ground
break into a conversation
intrude on uninvited
enter someone's (virtual or real) property in an unauthorized manner, usually with the intent to steal or commit a violent act