Some prepositions, called compound prepositions, are made up of more than one word, such as according to, because of, in front of, instead of, in spite of, and next to.
Confusing use of prepositions
The unnecessary use of prepositions is a common error. Be careful not to use a preposition where it isn't needed.
Also, don't use two prepositions when you need only one.
Ending a sentence with a preposition can cause problems. The rule that a sentence should never end with a preposition is no longer strictly enforced. Still, many writers avoid ending sentences with prepositions. If you feel ending with a preposition makes a sentence sound more natural, do so and don't worry about it.