break in (1. often no object; with an object, break into--inseparable): enter by using force (and breaking a lock, window, etc.)

"Jane's apartment was burglarized last night. Someone broke in while Jane was at the movies." / "Somebody broke into Jane's apartment while she was at the movies.

break in (2. separable): wear something new until it's / they're comfortable.

"These are nice shoes, but they're too stiff. I hope it doesn't take too long to breakthem in."

break in (3. separable): train; get someone / something accustomed to a new routine.

"I hope I can learn my new job quickly. The manager hasn't scheduled much time forbreaking me in."

break up (1. no object): disperse; scatter.

"What time did the party break up last night?"

break up (2. usually no object; with an object, break up with [inseparable)]): end a personal relationship.

"Tim and Julie aren't going steady any more. They got really angry with each other and broke up."

"Have you heard the news? Julie broke up with Tim!"

"I'm sorry to hear that their marriage broke up. I'm sure the divorce will be difficult for the children."

bring / take back (separable): return something.

"Yes, you can borrow my pen, don't forget to bring it back to me when you're finished."

"This book is due tomorrow. I guess I should take it back to the library."

bring off (separable): accomplish something difficult; accomplish something people had considered impossible or unlikely.

"No one thought Chuck could get an A in that course, but he brought it off. "

bring up (1. separable): mention (as a topic of discussion).

"We planned to discuss overtime pay in the meeting. Why didn't someone bring that topic up?"

bring up (2. separable): raise; rear.

"Lucy's parents died when she was a baby. Her grandparents brought her up."

brush up on (inseparable): review / study thoroughly for a short time.

"If you're going to travel to Peru, you'd better brush up on your Spanish."

burn down (no object): become destroyed / consumed by fire.

Note: For upright things--trees, buildings, etc.--only.

"Lightning struck Mr. Kennedy's barn last night. It burned down before the fire fighters arrived."

burn up (1. no object): become destroyed / consumed by fire.

Note: For people and non-upright things only.

"All of Mr. Kennedy's hay burned up when his barn burned down."

burn up (2. separable): cause someone to become very angry.

"Did you hear how rudely Fred talked to me? That really burned me up!"

butt in (no object): impolitely interrupt (a conversation, an action).

"Hey, you! Don't butt in! Wait for your turn!"

butter up (separable): praise someone excessively with the hope of getting some benefit.

"I guess Marty reall wants to be promoted. He's been buttering his boss up all week."

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