main noun, + preposition + whom + clause, + main clauseFormal pattern for people: move the preposition before whom.
Relative Clauses with Prepositions
C1In formal relative clauses, the preposition can move before whom or which: the person to whom I spoke. This pattern is common in careful written English.
What you'll learn
- Move the preposition before whom or which in formal clauses.
- Choose whom for people and which for things after the preposition.
- Add commas around non-defining clauses with fronted prepositions.
- Use this pattern when you want a formal written tone.
- Recognize common pairs like to whom and in which.
Structure
main noun, + preposition + which + clause, + main clauseFor things and ideas, use which after the fronted preposition.
name, + preposition + whom/which + clause, + main clauseIn non-defining clauses, commas show that the clause adds extra information.
Build a sentence
Preposition
Noun
themanagertowhomI wrotereplied today
The manager to whom I wrote replied today.
After a fronted preposition, choose whom for people.
When to use
Formal emails
Use it when you want a polished tone: The colleague with whom I met will contact you tomorrow.
Reports
This pattern fits formal summaries and reports: the procedure under which the team operates.
Extra information
Use commas when the clause only adds detail: Mr. Grant, to whom I had written, called me back.
Markers
to whomwith whomfor whomin whichon whichunder whichabout which
Common mistakes
Wrong
The person whom I spoke to was Anna.
Correct
The person to whom I spoke was Anna.
In this formal pattern, move the preposition before whom.
Wrong
The manager to who I wrote replied today.
Correct
The manager to whom I wrote replied today.
After a fronted preposition in formal style, use whom for people.
Wrong
The system on whom the team depends is offline.
Correct
The system on which the team depends is offline.
Use which, not whom, for things and systems.
Wrong
Mr. Lee with whom I spoke approved the plan.
Correct
Mr. Lee, with whom I spoke, approved the plan.
A non-defining clause adds extra information, so it needs commas.
Wrong
The colleague whom I worked is now in Dubai.
Correct
The colleague with whom I worked is now in Dubai.
This structure needs the preposition before whom or which.
Common misconceptions
❝ This pattern is wrong in modern English because people do not speak like this. ❞
It is fully correct. It is less common in casual speech, but it is natural in formal writing and careful presentations.
❝ If the clause is clear, I can use who after any preposition. ❞
After a fronted preposition in formal style, standard English uses whom for people and which for things.
Skills in this rule (5)
PUT_PREPOSITION_BEFORE_WHOM_WHICHw5Put the preposition before whom or which in formal relative clauses
In formal style, move the preposition to the front of the relative clause: the person to whom I spoke, the topic about which we argued.
CHOOSE_WHOM_FOR_PEOPLE_WHICH_FOR_THINGSw5Choose whom for people and which for things after a fronted preposition
After a preposition at the front, use whom for people and which for things or ideas: the client with whom we met, the policy under which they operate.
USE_NON_DEFINING_PUNCTUATIONw4Use commas around non-defining relative clauses with fronted prepositions
Add commas when the clause gives extra information, not the core identity: Mr. Lee, with whom I spoke, approved the plan.
USE_FORMAL_WRITTEN_STYLEw3Use fronted prepositions for a formal written tone
Choose this pattern in formal emails, reports, academic writing, and careful presentations when you want a more polished tone.
SPOT_COMMON_FRONTED_PREPOSITIONSw3Recognize common prepositions used in this pattern
Notice frequent pairs such as to whom, with whom, for which, in which, and under which in formal relative clauses.