Words such as to, from, over, and under show the relations between other words; these words are prepositions, and they are one of the more challenging elements of English writing. If you speak languages other than English, knowing which preposition your home language uses in an expression will not necessarily help you figure out which preposition to use in English. And if English is your home language, you may still choose the wrong prepositions from time to time in formal communication. Thus, you will almost certainly want to pay very careful attention to these little words.