In case you didn't know, I just wanted to add that people usually put the "grammatical object" in between the verb and the "up/down/on/off/etc." (especially when the object is replaced with the word "it"). It's more natural to say something like "pick it up" than "pick up it". Examples (that are used frequently in English): "Turn the lights off", "Turn the lights on", "She had lunch, but she threw it all up." Notes: if the "object(s)" consist of three or more words, then it usually sounds more natural to put it after the "up/down/off/on/etc." Example: "Pick up all your toys and dolls." :)

It looks like you are starting to discover English phrasal verbs. The first step is learning what they are an how to recognize them when you see them... The best approach is to study a few to understand how they work in English, then after that, focus on learning the phrasal verbs as you find them. I see many of my students trying to memorize a long list of phrasal verbs and in the end, they don't know how to use them or understand them anyway. Unfortunately, there are no official rules about when to use 'up' with a verb or how it affects the meaning. I often recommend a dictionary to my students called: http://context.reverso.net/ You can enter the phrasal verb (or any word or phrase) into this dictionary and you will see several sentences where it is used in English. If there is an option to translate it into your own language, that's even better, but it is still possible to use this dictionary tool to help you understand the meaning by seeing the phrase used in many different ways. For example 'break up' http://context.reverso.net/translation/english-spanish/break+up

Yes, phrasal verbs often don't make a lot of sense! There are a lot: Throw up (be sick) Show up (to attend something) Turn up (make something louder. OR the same as 'show up') Head up (to manage a team or project. OR go upstairs) Run up (to run up a bill. Order or buy a lot of things) Hit up (this is definitely a slang term, though. 'I am going to hit her up for something' I will ask her for something) Blow up. (To explode) Catch up (you were late or behind but you 'catch up' and join the faster people.) Bump up. (You can bump up the price- make it more expensive) The list goes on. They usually have a general relation to upward motion. But you just have to learn them as you come across them I'm afraid.

You just read about phrasal verbs with 'up'