Some languages add prefixes, infixes or suffixes to verbs to change the meaning. For example, in Russian the word for “go” can change through prefixes into “go in,” “go out,” “go around,” “go across,” “go over,” “go under” and so on. Each one is still a single word.
English, however, frequently adds a preposition after a verb to change the verb’s meaning. These are called phrasal verbs. (Phrasal verbs can also be constructed with adverbs.)
Some verbs have drastically different meanings depending on the preposition — or prepositions; there can be more than one — that follows.
For instance, you put your cards on the table. You put up money before the poker game, and put in your ante before each hand. You put down your friend who fidgets every time she has a good hand, but gently, so she doesn’t get put out. You put up with her cousin at the game because you need him to round out the group after another member put in for a transfer at work and moved to Peoria. You put away the cards when you’re done.
This is one reason you don’t need to worry about ending a sentence with a preposition: Many “prepositions” that are part of phrasal verbs don’t really function as prepositions. Some don’t even take objects.
Choose your prepositions carefully, making sure what you write is truly what you intend. And feel free to position the preposition at the end.