Back up - to provide support or help to someone
Cheer up - to feel encouraged and happier
Brush up - to refresh your knowledge on something
Bottle up - to refuse to talk about unpleasant things
Keep up - to understand and follow fast changes
Beat up - to hit someone hard and repeatedly
Dress up - to put on elegant clothes for an event
Own up - to admit you have made a mistake
Break up - to come to an end
Hold up - to steal using violence or threat
