Prepositions at sentence ends

Do not use a preposition to end a sentence with. That is an academic joke. Not very funny, is it?

The point is that the word 'preposition' means 'placed in front of'. (Prepositions are such short words as in, of, to, etc. which are used to show the relationship of a noun to other words, or to the rest of the sentence. Their meaning is not always very strong, and their use often depends on the idioms of natural native English). Because they are 'placed in front', you should not use them at the end of a sentence. Winston Churchill, who won the Nobel Prize for Literature, said famously that such a use of prepositions was "something up with which I will not put." That is another joke.

In general, try to avoid ending a sentence with a preposition. It is more elegant. But as another great writer, George Orwell, said in his rules of style, it is better to break such a rule than to write anything unnatural or ugly.