We spoke to the caretaker becomes Who did you speak to? The person is missing, but to stays. You can put some prepositions before the question word in a more formal pattern: To whom did you speak?
A preposition is a word such as to, from, with, for or about. It links information: a person you speak to, a place you come from, or a topic you read about. When you ask about the person, place or thing after the preposition, you need to keep that relationship.
| Statement | Information you want | Question |
|---|---|---|
| The parcel is for Amira. | the person it is for | Who is the parcel for? |
| We talked about the timetable. | the topic | What did you talk about? |
| They arrived from Helsinki. | the starting place | Where did they arrive from? |
In a statement, the preposition normally comes before a noun or pronoun: for Amira, about it. In these questions, the question word moves to the front and the preposition stays later in the sentence. This is called preposition stranding. You do not need the label to use the pattern.
Ending a question with a preposition is not a grammar error. British Council teaches this as the usual pattern for questions with verbs and prepositions. Cambridge describes it as common in informal styles, especially speech.
Start with the question word or phrase. Use the normal question order after it. In a present or past simple question with most main verbs, use do, does or did before the subject, then the base verb. Keep the preposition that belongs to the meaning.
With a continuous or perfect form, or a modal such as can, keep that helper instead of adding do. If be is the main verb, put be before the subject without adding do.
| Pattern | Question | What to notice |
|---|---|---|
| continuous | Who are the children playing with? | are before the children; playing stays |
| perfect | What has the panel agreed on? | has before the panel; agreed stays |
| modal | Which entrance can we go through? | can before we; go stays |
| main verb be | What is the presentation about? | is before the presentation |
There may be more words between the main verb and the final preposition. In Who did you lend the camera to?, the camera stays as the direct object of lend. The question asks about the person after to. Do not delete the camera or change the question to Who lent the camera? That asks about a different person: the lender.
End position is a useful basic description, not a demand that the preposition be the very last printed word. Another phrase can follow it: Who did you sit beside during the lecture? The preposition beside is separated from its missing person; during the lecture adds time information.
Do not choose the preposition just because the question starts with who or what. Start with the statement you could answer with. A change of preposition can change the relationship you ask about.
| Answer pattern | Question | Relationship |
|---|---|---|
| The letter is from our solicitor. | Who is the letter from? | sender |
| The letter is for our solicitor. | Who is the letter for? | intended recipient |
| They walked with their neighbour. | Who did they walk with? | companion |
| They talked about their neighbour. | Who did they talk about? | topic |
Some prepositions belong to a verb pattern: listen to, depend on, wait for. Some follow an adjective: interested in, worried about. A question keeps the preposition for that pattern. This is why What are you interested in? has in even though interested is not the main action verb.
Use a learner's dictionary when you are not sure which pattern expresses your meaning. This page explains where the preposition goes; it cannot replace the separate meanings of all verb and adjective combinations. See Verb + preposition and Adjective + preposition.
Where asks about a place. A preposition can make the relationship more exact. Where are the visitors from? asks about origin. Where are the visitors going? asks about destination.
Where does not require a final preposition in every question. Where is the pharmacy? already asks for its location. Do not add from unless you want an origin, or to unless the meaning involves a destination. Choose a question that matches the information you need.
A longer phrase such as which town contains a noun and fits after a fronted preposition too: To which town are they travelling? That is a more formal way to ask the same destination question.
With suitable question words and phrases, you can put the preposition before them. Cambridge describes this as more formal. It is a style choice, not a repair for a faulty end-position question.
| End-position pattern | More formal fronted pattern |
|---|---|
| Which account did you pay from? | From which account did you pay? |
| What is the disagreement about? | About what is the disagreement? |
| Which year was the bridge built in? | In which year was the bridge built? |
Keep the preposition once, not twice. If you move from to the front in From which account did you pay?, do not leave another from at the end.
Fronting is not a rule that every sentence-final word can follow. A particle in a phrasal verb is different; see the comparison below. The formal examples here demonstrate usable patterns, not permission to move any word in any expression.
Who is used for people in ordinary questions with a final preposition: Who did the manager send the invitation to? In a more formal style, whom is an object form referring to a person. You can leave the preposition at the end or put it directly before whom.
| Pattern | Example |
|---|---|
| ordinary who, preposition later | Who did you receive the instructions from? |
| formal whom, preposition later | Whom did you receive the instructions from? |
| more formal fronted preposition | From whom did you receive the instructions? |
After a directly fronted preposition, use whom rather than who in this formal standard pattern. Do not teach that whom must always take a preposition in front of it: Cambridge also gives the whom... to pattern with the preposition at the end.
Whom is not the subject form. Compare Who sent the instructions?, which asks about the sender, with Who did you send the instructions to?, which asks about the recipient. The presence of who does not by itself tell you whether you have a subject question. See Subject and object questions.
Which, what and whose can be part of a phrase containing a noun. Keep the whole phrase together. Whose asks about possession, but the preposition still tells you how that person or thing fits into the sentence.
In the office examples, the missing information identifies an owner. It does not identify the person who conducted the interview. In the team example, against tells you that you want the opponents, not the team the players belong to.
In conversation, you can leave out words that the other person can recover from the situation. A short question may contain only a question word and a preposition.
Cambridge gives these short stranded patterns, but it also gives At what time? with the preposition first. Do not make a rule that all short questions put the preposition last. Learn the short phrase as a usable unit.
Your reply can repeat the preposition, or give only the missing information when that is clear. After Who is the parcel for?, For Amira and Amira both identify the recipient. A complete answer is The parcel is for Amira.
An embedded question is a question inside a longer sentence. The inside part uses statement order: subject before verb. Do not keep direct-question do just to form that inside question.
The preposition is still needed. A more formal embedded pattern can put it before the question phrase: Can you tell me from which platform the train leaves? The inside clause still has statement order: the train leaves, not does the train leave. For punctuation and more patterns, see Embedded questions: do you know where..., I don't know what....
A particle is a small word that forms part of a phrasal verb, such as up in wake up. It is not functioning like from in a question about an origin. Keep it with its verb pattern.
Do not write Up when did your brother wake? to make this question more formal. Cambridge explicitly distinguishes this from preposition fronting. Moving a noun object around a particle is a different issue from putting a preposition before a question word.
✗What did the guide talk about about?
✓What did the guide talk about?
Keep one about, not two.
✗Which project did the team worked on?
✓Which project did the team work on?
After did, use the base verb work.
✗In which room are the guests staying in?
✓In which room are the guests staying?
The fronted in already supplies the preposition. Do not repeat it.
✗Do you know who is this envelope for?
✓Do you know who this envelope is for?
The embedded part uses subject before verb: this envelope is.
Use Question forms: yes/no and wh- questions for question order and Subject and object questions for the missing person's role. Use Verb + preposition and Adjective + preposition to choose a pattern. Compare Prepositions in relative clauses: with whom, which... with for prepositions in relative clauses, which are not questions.
Eight questions. Choose one answer for each.