Ending A Sentence With A Preposition

In my early years teaching ESL, I once had a student raise her hand and ask, “Teacher, is it really wrong to end a sentence with a preposition?” Her textbook had marked it as an error, but in every movie and conversation she heard outside class, native speakers did exactly that. That moment taught me something important: the rule against ending sentences with prepositions is one of the most misunderstood “rules” in English grammar. The truth is far more nuanced than most learners are taught.

The short answer is this: ending a sentence with a preposition is completely acceptable in modern English, especially in informal and even many formal contexts. I’ll walk you through when it’s fine to do so, when you might want to avoid it, and — most importantly — why this “rule” isn’t really a rule at all.

The Origins of the “No Prepositions at the End” Rule

The prohibition against ending a sentence with a preposition traces back to the 17th century, but it really took hold in the 18th. The most influential figure was Robert Lowth, an Anglican bishop who published a popular grammar book in 1762. Lowth declared that ending a sentence with a preposition was incorrect, and his position spread rapidly through schools and textbooks.

Here’s the problem: Lowth based this rule on Latin grammar, not on how English actually works. In Latin, prepositions must come before their objects — “de quo” (about whom), never “quo de” (whom about). English, however, evolved differently. English has always allowed prepositions to come at the end of sentences, and has done so for centuries.

Example: Shakespeare and Jane Austen — two of the most respected writers in the English language — regularly ended sentences with prepositions. Yet somehow, this usage got labeled “incorrect.”

When Ending Sentences with Prepositions Is Not Only Acceptable But Required

With Phrasal Verbs

Phrasal verbs are verbs made of a main verb plus a preposition or adverb particle. The preposition is an integral part of the verb, not a separate element you can move around.

Example: “I’m going to find him out” — this sounds broken. The correct form is “I’m going to find out him,” but even better is “I’m going to find him out.” Wait — no. The natural way is: “I’m going to find him out.” Actually, let me be clear: with “find out,” the correct pattern is “I found out the truth” (object in the middle) or the passive form “The truth was found out.” But in questions: “What did you find out?” The preposition stays at the end.

Here are common phrasal verbs where the preposition naturally ends up at the end:

• Look up: “Have you looked it up?” (not “Have you up-looked it?”)
• Give in: “Will you ever give in?” (natural ending)
• Put off: “Why do you put it off?” (preposition at the end, and it’s fine)
• Take on: “Who are you going to take on?” (natural position)
• Run into: “Who did you run into?” (question with preposition at end)

Trying to move these prepositions to the beginning makes English sound artificial: “For what are you looking?” works, but “What are you looking for?” is how native speakers actually speak.

In Questions

Questions with interrogative words (what, where, who, whom, whose, why, how) very naturally end with prepositions:

• “What are you looking at?” (natural and correct)
• “Where did you come from?” (no one says “From where did you come?”)
• “Who are you talking to?” (standard usage)
• “What is this book about?” (very common)
• “Which table do you prefer to sit at?” (ends with a preposition, completely natural)

Example dialogue: A student might ask her teacher, “What tense should I use in this situation?” Notice the preposition “in” at the end? That’s natural, correct English. Rephrase as “In which situation should I use this tense?” and it sounds stiff and overly formal.

In Informal Writing and Speech

In emails, text messages, casual conversation, and most professional communication, ending a sentence with a preposition is completely appropriate. The goal is clear, natural communication — not adherence to a rule that contradicts how English evolved.

Example: “I can’t remember who that book was written by” — perfectly acceptable and natural. The formal alternative, “By whom was the book written?” sounds stilted in most modern contexts.

When You Might Choose to Avoid It (But It’s Not an Error)

For Emphasis or Formality

In highly formal academic papers or legal documents, you might choose to restructure a sentence to avoid an ending preposition — not because it’s wrong, but because it creates a particular tone. “For what are you waiting?” sounds more formal than “What are you waiting for?” — but both are correct.

For Clarity

In rare cases, a sentence might be clearer if you move the preposition. For example:

Less clear: “This is the project everyone is talking about.”
Clearer: “This is the project that everyone is discussing.” (avoids “about” at the end and strengthens the verb)

But notice: the improvement is about word choice, not grammar.

Common Mistakes Learners Make

✓ Correct: What are you looking for?
✗ Incorrect: What are you looking? (incomplete; “for” is essential)
Why: In this question, “for” is part of the phrasal verb “look for” and must be included. Removing it changes the meaning.

✓ Correct: I don’t know who she’s talking to.
✗ Incorrect: I don’t know who she’s talking. (incomplete)
Why: The verb “talk” requires “to” as a preposition when followed by a person. Without it, the sentence is unfinished.

✓ Correct: This is something I’ve never heard of.
✗ Incorrect: This is something I’ve never heard. (incomplete)
Why: “Heard of” is a set phrase. You “hear of” something (learn about it indirectly), so the preposition belongs at the end, where it naturally sits.

Sample Dialogue: At the Language Exchange

Quick Practice Quiz

Related Articles on English Prepositions

• Prepositions of Time: In, On, At, By, During, For
• Prepositions of Place: In, On, At, and Beyond
• Phrasal Verbs: Complete Guide with 50+ Examples
• Common Preposition Mistakes and How to Avoid Them
• ↑ Back to pillar: English Prepositions (Pillar)

Frequently Asked Questions

Related

• ↑ Master Pillar: English Grammar

Quick Test: Check Your Understanding

5 questions to test what you've learned. No sign-up required.

Loading quiz…