Here’s an example of a sentence that can end with a preposition: What did you step on? A key point, you might say the Quick and Dirty Tip, is that the sentence doesn’t work if you leave off the preposition. You can’t say, “What did you step?” You need to say, “What did you step on?” to make a grammatical sentence.
I can hear some of you gnashing your teeth right now, while you think, “What about saying, ‘On what did you step?’” But really, have you ever heard anyone talk that way? I’ve read long, contorted arguments from noted grammarians about why it’s OK to end sentences with prepositions when the preposition isn’t extraneous (1), but the driving point still seems to be, “Nobody in their right mind talks this way.” Yes, you could say, “On what did you step?” but not even grammarians think you should.
A couple from Georgia and a couple from the Northeast were seated side by side on an airplane.The girl from Georgia, being friendly and all, said, “So, where y’all from?”The Northeast girl said, “From a place where they know better than to use a preposition at the end of a sentence.”The girl from Georgia sat quietly for a few moments and then replied: “So, where y’all from, bitch?” (Joke: Daniel Miessler)