Ending with a preposition
Contrary to popular wisdom, you are allowed to end a sentence with a preposition. The noun or pronoun (the object of the preposition) can usually be found earlier in the sentence:
You are the only person I am showing this to.
Which of those girls are you going on a date with?
Check out the treasure we stumbled upon.
Most of the time, though, you can reword the sentence to avoid ending on a preposition.