to break up	1 to begin school holidays, 2 to disintegrate,3 of weather 4 a car etc
to break up a fight	to interrupt and stop it
the outbreak	the beginning of sth bad, like wars, fires etc
to break oneself of a habit	to force oneself to give habit up
to break with someone	to stop having anything to do with someone
to break with tradition	to do sth quite different or new
to break the news to someone	to tell someone some bad news as gently as possible
to break the back of sth	I have done most of it and all the hardest part
to break through	eg sun, it has appeared through the clouds
a break-through	a major discovery in research etc
a lucky break	a stroke of luck, generally for a criminal
to drive at breakneck speed	to drive dangerously fast