Formal Prepositions: To Whom or Who To? (Pied-Piping)
Grammar Rule in 30 Seconds
Pied-piping moves a preposition to the front of a relative clause for high-level formality, while stranding leaves it at the end.
- In formal writing, place the preposition before 'whom' or 'which' (e.g., 'The person to whom I spoke').
- In casual speech, leave the preposition at the end (e.g., 'The person I spoke to').
- Never use 'that' or 'who' immediately after a preposition; always use 'whom' or 'which'.
Overview
English has many rules. Some rules make you sound very formal.
This style is for serious books and big speeches. Experts use it.
Long ago, English was different. This style sounds very smart today.
It helps you write clear and very good sentences.
How This Grammar Works
Formation Pattern
which she referred to. | The report to which she referred. |
who he spoke with. | The committee with whom he spoke. |
that they aimed for. | The objective for which they aimed. |
where I was working in. | The context in which I was working. |
When To Use It
- Academic Writing: In university essays, research papers, theses, and scholarly articles, pied-piping is often expected. It contributes to the objective and authoritative tone. For instance,
The theoretical framework upon which this analysis is built requires careful considerationsounds more academic thanThe theoretical framework which this analysis is built upon.This structure enhances the coherence of complex arguments. - Legal and Official Documents: Contracts, statutes, official reports, and policy papers frequently employ pied-piping to ensure absolute clarity and to avoid any potential ambiguity. Legal texts demand rigorous precision, and pied-piping aids in establishing unequivocal relationships between clauses. Phrases like
The terms under which the agreement was signedare standard. - Formal Speeches and Presentations: When delivering a formal address, lecturing, or participating in a high-level debate, using pied-piped constructions elevates the discourse. It conveys professionalism and respect for the audience and the subject matter. A presenter might say,
The challenge with which we are faced is significant,projecting an educated and meticulous style. - Literary Prose: Authors aiming for a sophisticated, traditional, or elegant style, particularly in narrative or descriptive passages, may use pied-piping. It can evoke a classical feel or reflect the educated voice of a character.
The ancient manor, within whose walls many secrets lay hidden, stood silent. - Reducing Ambiguity in Complex Sentences: In instances where a preposition stranded at the end of a long clause might momentarily confuse the reader or listener about which verb it belongs to, pied-piping can clarify the syntactic connection immediately. By fronting the preposition, the dependency is made explicit, streamlining comprehension for complex information.
The complex interdependencies among which the various factors operate are difficult to isolate.
Common Mistakes
- Confusion between
whoandwhom: This is arguably the most frequent mistake. In formal English, after a preposition, the objective case pronounwhommust be used when referring to people. Usingwho(the nominative case) immediately after a preposition is grammatically incorrect in pied-piped constructions. You would not sayThe manager to who I report; it must beThe manager to whom I report.A useful diagnostic: if you can replace thewh-phrase withhimorher(objective pronouns), thenwhomis correct. If you replace it withheorshe(subjective pronouns), thenwhois correct. Thus,to himcorrectly correlates toto whom. - Overuse and Misapplication in Informal Contexts: Forcefully integrating pied-piped structures into casual conversation or informal writing makes your language sound unnaturally stiff and pretentious. C2 proficiency involves knowing when not to use a complex structure as much as knowing how to use it. A text message saying
To whom are you sending that emoji?would be perceived as affected and out of place. - Pied-piping
that: As previously stated,thatcannot be pied-piped. Any construction likeThe issue about that I am concernedis ungrammatical. Always substitutewhichorwhomwhen a preposition precedes the relative pronoun. - Incorrect
wh-wordChoice: Usingwhichto refer to people instead ofwhom(e.g.,The student with which I studied) is incorrect. Similarly, usingwhomfor inanimate objects (e.g.,The book from whom I learned much) is an error. Maintain the distinction:whomfor people,whichfor things/ideas. - Inappropriate Preposition Choice: While not strictly an error of pied-piping, sometimes an incorrect or unidiomatic preposition is chosen, leading to awkward phrasing. For example,
The situation on which he elaboratedmight be grammatically correct, butThe situation about which he elaboratedorThe situation upon which he elaboratedmight be more idiomatic depending on the context and desired nuance. - Confusing
whoseandwho's: Whilewhosecan occasionally appear in pied-piped structures, the homophonewho's(a contraction ofwho isorwho has) can lead to errors in formal writing. Always rememberwhoseindicates possession, whilewho'sis a verb contraction.The author whose book...vs.The author who's writing....
Real Conversations
Despite its formal nature, pied-piping is not confined solely to dusty legal tomes. It is actively used in modern, high-register communication. Recognizing these patterns demonstrates an acute awareness of English's nuanced capabilities.
- Professional Correspondence (Email):
- Dear Ms. Jenkins, regarding the proposal to which you referred in your previous email, we have conducted a thorough review. (Formal business communication)
- Academic Discussion (Seminar):
- The methodology upon which these findings are based warrants further scrutiny, particularly concerning the ethical implications with which such research is fraught. (Scholarly discourse)
- News Reporting (Formal Interview):
- The Prime Minister, to whom the question was directed, reiterated the government's commitment to the new policy. (Impartial and formal reporting)
- Legal Proceedings (Courtroom):
- The defendant, against whom a compelling body of evidence was presented, remained stoic. (Precise legal language)
- Literary Adaptation (Historical Drama Dialogue):
- This arduous journey, for which we have prepared so long, begins at dawn. (Elevated dialogue reflecting a historical setting)
These examples illustrate that pied-piping is a functional tool for clarity and formality, not merely an archaic grammatical quirk. In C2 contexts, its presence signifies a deliberate choice to align language with the seriousness or intellectual demands of the communication. It reflects a cultural expectation in certain professional and academic spheres that language should be as precise and unambiguous as possible.
Quick FAQ
- Q: What exactly is
pied-pipingin grammar?
Pied-piping is a formal grammatical construction in which a preposition is positioned immediately before a wh-word (like whom, which, whose) at the beginning of a relative clause, rather than being left at the end of the clause. For example, The person to whom I spoke is pied-piped, while The person I spoke to is not.
- Q: When should I use
whominstead ofwhoafter a preposition?
In formal English, when a preposition directly precedes a relative pronoun referring to a person, you must use whom. This is because prepositions govern the objective case, and whom is the objective form of who. Always use constructions like for whom, with whom, by whom, etc.
- Q: Is it always incorrect to end a sentence with a preposition?
No, this is a common misconception based on prescriptive rules from Latin grammar. In modern, everyday English, preposition stranding (ending a clause or sentence with a preposition) is perfectly natural, common, and grammatically acceptable. For example, Who are you talking to? is standard in informal contexts. The choice depends entirely on the desired level of formality.
- Q: Can I use pied-piping with the relative pronoun
that?
No, you cannot. That cannot combine with a preceding preposition in a pied-piped relative clause. Structures such as The problem about that I am worried are ungrammatical in English. You should use which instead: The problem about which I am worried.
- Q: Does pied-piping always make sentences clearer or easier to understand?
While pied-piping can enhance clarity by explicitly linking a preposition to its object early in a clause, particularly in complex sentences, it can also make sentences sound more formal or dense to readers unaccustomed to the structure. Its primary function is often stylistic—to elevate the register—rather than solely to simplify comprehension.
- Q: What's a simple diagnostic test to remember when to use
whomin pied-piping?
Replace the wh- phrase and its preceding preposition with a personal pronoun. If him or her fits naturally, then whom is correct. If he or she fits, then who would be correct if a preposition were not present (though who would not be used after a preposition in formal pied-piping). For example, (To him) I spoke implies To whom I spoke.
- Q: Is pied-piping exclusively for written English?
Predominantly, yes. However, it does appear in very formal spoken contexts, such as academic lectures, political addresses, formal interviews, and high-level professional presentations. Its presence in spoken language is a strong indicator of a highly educated and formal register, often reserved for planned and deliberate speech.
Pied-Piping vs. Stranding Structures
| Register | Relative Pronoun | Preposition Position | Example |
|---|---|---|---|
|
Formal
|
Whom / Which
|
Before Pronoun
|
The person to whom I spoke.
|
|
Neutral
|
Who / Which / That
|
End of Clause
|
The person who I spoke to.
|
|
Informal
|
None (Omitted)
|
End of Clause
|
The person I spoke to.
|
|
Very Formal
|
Whose + Noun
|
After Preposition
|
The man in whose house we stayed.
|
Meanings
Pied-piping is a linguistic phenomenon where a preposition is 'dragged' to the front of a relative clause along with the relative pronoun, creating a highly formal tone.
Formal Pied-Piping
The movement of a preposition to the position immediately preceding a relative pronoun (whom/which).
“The committee to whom the report was submitted has yet to comment.”
“This is the methodology by which we achieved our results.”
Preposition Stranding
Leaving the preposition at the end of the clause, often omitting the relative pronoun or using 'that'.
“The person I was talking to just left.”
“That is the book I was looking for.”
Interrogative Fronting
Using pied-piping in direct questions to signal extreme professional distance or authority.
“With whom do you wish to speak?”
“To what do I owe the pleasure?”
Reference Table
| Form | Structure | Example |
|---|---|---|
|
Affirmative (Formal)
|
Prep + Whom/Which
|
The case in which we are interested.
|
|
Affirmative (Informal)
|
That/Zero + ... + Prep
|
The case (that) we are interested in.
|
|
Question (Formal)
|
Prep + Whom/Which + Aux
|
To whom were you speaking?
|
|
Question (Informal)
|
Who/What + ... + Prep
|
Who were you speaking to?
|
|
Negative (Formal)
|
Prep + Whom + Neg. Verb
|
The man to whom I did not speak.
|
|
Possessive (Formal)
|
Prep + Whose + Noun
|
The author from whose book I quoted.
|
|
Place (Formal)
|
Prep + Which
|
The city in which I was born.
|
|
Time (Formal)
|
Prep + Which
|
The year in which it happened.
|
Formality Spectrum
To whom are you speaking? (Communication)
Who are you speaking to? (Communication)
Who are you talking to? (Communication)
Who you on the phone with? (Communication)
The Pied-Piping Movement
Formal (Front)
- To whom To whom
- In which In which
Informal (End)
- ...to ...to
- ...in ...in
Register Shift
Should I Pied-Pipe?
Is this a formal document?
Is it a casual chat?
Forbidden Combinations
Never Use
- • To who
- • In that
- • With that
- • For who
Examples by Level
Who are you talking to?
Who is this gift for?
Which bus are you on?
Who do you live with?
This is the house I live in.
Who did you go to the cinema with?
That is the man I was looking for.
What are you thinking about?
The company I work for is very big.
He is the person I told you about.
This is the tool I use it with.
The hotel we stayed at was cheap.
The person to whom you should speak is Mr. Smith.
The method by which we solve this is simple.
With whom are you attending the gala?
The reasons for which he resigned are unknown.
The framework within which the policy was developed is robust.
To whom it may concern, I am writing to complain.
The speed at which the virus spreads is alarming.
The individual from whom I received the tip remains anonymous.
The socio-economic climate in which these ideas germinated was volatile.
It is a principle to which we must all adhere, regardless of cost.
The degree to which she was involved remains a matter of debate.
The medium through which the message is conveyed alters its meaning.
Easily Confused
Learners often use 'who' after a preposition because 'whom' feels archaic.
Learners try to use 'that' in formal pied-piping.
Learners try to pied-pipe phrasal verbs like 'look after'.
Common Mistakes
To who are you talking?
Who are you talking to?
The man which I see.
The man who I see.
Who you talk to?
Who are you talking to?
I talk to he.
I talk to him.
The house in that I live.
The house I live in.
Who did you go with him?
Who did you go with?
The book what I read.
The book I read.
The person to who I gave the money.
The person to whom I gave the money.
The company which I work.
The company I work for.
The friend with who I went.
The friend I went with.
The problem into which he ran.
The problem he ran into.
The room in which I stayed in.
The room in which I stayed.
The person whom I spoke to.
The person I spoke to.
Sentence Patterns
The ___ in which I ___ is ___.
He is a person to whom ___.
The degree to which ___ depends on ___.
There are several ways by which ___.
Real World Usage
The terms under which this agreement is terminated...
The participants to whom the survey was sent...
The team with which I collaborated most closely...
Who are you with?
The government to which we are accredited...
The person I'm obsessed with!
The 'Him' Test
Avoid Hypercorrection
Which for Things
Churchill's Rule
Smart Tips
Check your relative clauses. If you see a preposition at the end, try moving it to the front with 'which' or 'whom' to sound more professional.
Try the 'Him Test'. If you can answer with 'him', use 'whom'.
Be careful! Some phrasal verbs sound very strange when pied-piped. If it sounds weird, just leave the preposition at the end.
Stop! 'In that' is only used as a conjunction meaning 'because'. It is never a relative clause. Change it to 'in which'.
Pronunciation
Whom vs. Who
In 'To whom', the 'm' is often soft and links to the next vowel.
Preposition Stress
In pied-piping, the preposition is usually unstressed. In stranding, it often carries a slight stress at the end of the sentence.
Formal Falling
To whom should I address this? ↘
Conveys authority and finality.
Memorize It
Mnemonic
The Pied Piper leads the preposition to the front of the parade (the sentence).
Visual Association
Imagine a tiny preposition (like 'to' or 'with') holding onto the tail of a large 'Whom' as they march to the front of a line of words.
Rhyme
If the preposition comes before, 'Whom' and 'Which' are at the door.
Story
A lawyer named Mr. Whom always carries his briefcase (the preposition) in front of him. His brother, Who, is messy and leaves his briefcase at the end of the hallway.
Word Web
Challenge
Write three sentences about your job using 'in which', 'to whom', and 'by which'.
Cultural Notes
Pied-piping is slightly more common in high-level British English than in American English, especially in the BBC or traditional broadsheets.
U.S. legal documents are famous for 'legalese' which relies heavily on pied-piping to avoid any ambiguity in contracts.
Globally, academic journals prefer pied-piping to maintain an impersonal, objective tone.
Pied-piping is a result of 17th and 18th-century grammarians (like John Dryden) attempting to align English with Latin grammar, where prepositions never ended a sentence.
Conversation Starters
In your opinion, what is the most important value to which a leader should adhere?
Tell me about a person from whom you have learned a great deal.
What are the main goals for which you are currently striving?
Is there a specific city in which you would love to live?
Journal Prompts
Common Mistakes
Test Yourself
Which of these is correct for a legal document?
The speed ___ ___ the car was traveling was excessive.
Find and fix the mistake:
The house in that he was born is now a museum.
The people ___ ___ I work are kind.
You can omit the relative pronoun in a pied-piped clause (e.g., 'The man to I spoke').
Select the valid pronouns.
Judge: '___ ___ are you referring?' Lawyer: 'I am referring to the defendant.'
which / the / in / case / we / interested / are
Score: /8
Practice Exercises
8 exercisesWhich of these is correct for a legal document?
The speed ___ ___ the car was traveling was excessive.
Find and fix the mistake:
The house in that he was born is now a museum.
The people ___ ___ I work are kind.
You can omit the relative pronoun in a pied-piped clause (e.g., 'The man to I spoke').
Select the valid pronouns.
Judge: '___ ___ are you referring?' Lawyer: 'I am referring to the defendant.'
which / the / in / case / we / interested / are
Score: /8
Practice Bank
12 exercisesThe committee ___ the proposal was presented reviewed it thoroughly.
She's the professor who I wrote my thesis with.
Which sentence is correct?
Translate into English: 'El documento al que se refirió es confidencial.'
Arrange these words into a sentence:
Match the informal phrases with their formal counterparts:
The circumstances ___ he found himself were dire.
The esteemed panel, who we sent the feedback to, will reconvene tomorrow.
Which sentence is correct?
Translate into English: 'Ella es la candidata en quien confiamos.'
Arrange these words into a sentence:
Match each preposition with its formal partner:
Score: /12
FAQ (8)
No, it is a myth. Ending with a preposition (stranding) is perfectly correct and often more natural in English. Pied-piping is just a formal stylistic choice.
Use `whom` whenever it follows a preposition (e.g., 'to whom') or when it is the object of a verb in formal writing.
No. If you move the preposition to the front, you *must* use `whom`. 'To who' is considered a grammatical error even in semi-formal speech.
Linguist John R. Ross named it after the Pied Piper of Hamelin because the relative pronoun 'pulls' the preposition along with it to the front of the clause.
Yes. You can say 'The man in whose house we stayed.' This is a very formal version of 'The man whose house we stayed in.'
Never. You cannot say 'The house in that I live.' You must use `which` or strand the preposition: 'The house that I live in.'
Yes, it remains the standard formal salutation for letters when the recipient's name is unknown.
Only use pied-piping in writing or very formal speeches. In 95% of daily conversations, stranding the preposition is the better choice.
Scaffolded Practice
1
2
3
4
Mastery Progress
Needs Practice
Improving
Strong
Mastered
In Other Languages
con el que / a quien
English allows stranding; Spanish does not.
avec lequel / auquel
French relative pronouns change based on gender/number (lequel/laquelle).
mit dem / worüber
German uses cases (Dative/Accusative) after the preposition.
Relative clause + Noun
Japanese uses particles that stay with the verb inside the clause.
Resumptive pronouns
English forbids the extra pronoun at the end.
...的 (de)
No movement of prepositions exists in Chinese relative structures.
Learning Path
Prerequisites
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