Advanced relative clauses (using 'whom', 'whose', and complex structures)

What is a relative clause and when do I use one?

A relative clause is a clause (it has a verb) that modifies a noun or noun phrase. It gives extra information about a person, thing, time, place, or idea. Relative clauses usually begin with a relative pronoun (who, whom, whose, which, that) or a relative adverb (where, when, why).

- The teacher who teaches Chemistry is from Brazil. (The clause "who teaches Chemistry" describes which teacher.)
- My car, which I bought last year, already needs a repair. (The clause "which I bought last year" adds extra information about my car.)

Key idea: A relative clause links information to a noun (its antecedent). It can be essential (restrictive) or extra (non-restrictive). You choose the structure and punctuation depending on meaning and register (formal vs informal).

Restrictive vs non-restrictive: what's the difference?

- Restrictive (defining) relative clauses are essential: they identify which person or thing we mean. They are NOT set off with commas.
- Example: The students who study hard pass the test. (Only those students pass.)

- Non-restrictive (non-defining) relative clauses give extra information about a noun already identified; they ARE set off with commas and cannot use "that".
- Example: My sister, who lives in Boston, is visiting. (I have one sister; the clause adds extra info.)

Who and Whom: how do I choose between them?

Who vs whom — subject or object?

- Use who when the relative pronoun is the subject of the relative clause.
- The man who called you left. ("who" = subject: he called you.)

- Use whom when the relative pronoun is the object of a verb or preposition in the relative clause.
- The man whom you called left. ("whom" = object: you called him.)

Quick test: Replace the relative pronoun with he/him (or she/her). If "he/she" fits, use who. If "him/her" fits, use whom.

- The woman who answered the phone is my neighbor. -> She answered the phone. (subject → who)
- The woman whom I called is my neighbor. -> I called her. (object → whom)

When is 'whom' necessary and when can I use 'who' instead?

- In spoken, informal English, many speakers use who in place of whom. That is common and accepted in conversation.
- In formal writing and after fronted prepositions, using whom is clearer and preferred:
- Formal: To whom did you speak?
- Informal: Who did you speak to? / Who did you speak with?

Examples:
- Formal: The person to whom I gave the letter is away. (preposition fronted)
- Informal: The person I gave the letter to is away. (preposition stranded; pronoun omitted)
- Incorrect: She is the person whom lives next door. (wrong — "whom" is used as subject; use who)

Whose: how do I express possession in relative clauses?

Using 'whose' with people and things

- "Whose" is the possessive relative pronoun. It usually refers to people, but it is commonly used for things as well.
- People: The student whose laptop was stolen reported it. ("whose laptop" = the student's laptop)
- Things: A house whose roof leaks needs repair. (Many speakers/writers accept this.)

- If you prefer to avoid "whose" with things in very formal writing, you can use "of which":
- The house, the roof of which leaks, needs repair. (more formal/wordy)

Examples:
- The author whose book won the prize will speak tonight. (person)
- I found a document whose date was missing. (thing — acceptable)
- More formal: I found a document, the date of which was missing.

Which and That: how to pick between them?

Which vs that — restrictive and non-restrictive use

- Use that for restrictive (essential) clauses in American English; use which for non-restrictive (extra) clauses.
- Restrictive (no commas): The book that has the torn cover is mine.
- Non-restrictive (commas): The book, which has a torn cover, is mine.

- British English sometimes uses which in restrictive clauses too, but in formal American English the guideline is: that = restrictive; which = non-restrictive.

Can 'that' refer to people?

- Yes, informally "that" can refer to people in restrictive clauses: The person that called was friendly. But "who" is more natural and preferred in formal contexts: The person who called was friendly.

Omitting the relative pronoun (contact clauses)

- When the relative pronoun is the object of the relative clause, you can often omit it in informal and neutral English.
- The song (that) I heard yesterday was great.
- The person (whom) I admire most is my teacher.

- You cannot omit the pronoun when it is the subject of the relative clause.
- Correct: The person who left is my friend. (subject — cannot omit)
- Incorrect: The person left is my friend. (missing subject)

Complex and nested relative clauses: how do they work?

Nested relative clauses: examples and analysis

Example 1:
- The book that the student who sits next to me recommended is excellent.
- Head noun: the book
- Outer relative clause modifying "book": that the student who sits next to me recommended
- Inner relative clause modifying "student": who sits next to me
- Reordered for clarity: The student who sits next to me recommended the book.

Example 2:
- The woman whose son the teacher praised left early.
- Head noun: the woman
- Relative clause: whose son the teacher praised ("whose son" = subject of the praise)
- Meaning: The woman's son was praised by the teacher; the woman left early.

Tips for reading complex clauses:
- Find the head noun first. Ask: Which noun is the clause describing?
- Look for nested "who/which/that/whose" phrases inside that clause.
- Rephrase the clause as a separate sentence to check meaning.

Relative clauses with verbs like 'believe', 'think', 'say' (and infinitives)

- Some verbs take an object + infinitive structure (e.g., believe, consider):
- I believe him to be honest. -> The man whom I believe to be honest is here.
- Here, "whom" is grammatically the object of believe but logically the subject of "to be honest." Formal writing often uses "whom" in this pattern.
- Alternative (less formal or simpler): I believe that he is honest. -> The man who I believe is honest is here.

- Use care: both forms can appear, and formality may determine whether you prefer "who" or "whom." If the structure is awkward, consider rephrasing.

Free (fused) relatives: what, whatever, whoever, whomever

- A free (fused) relative has no separate antecedent. It acts as a noun phrase on its own.
- What he said was surprising. ("what he said" = the thing that he said)
- Whoever arrives first will get a prize. (the person who arrives first)

Whoever vs whomever — how to choose:
- Decide the case inside the fused relative clause, not in the main clause.
- I will hire whoever/whomever you recommend.
- Inside: you recommend X → X is object of "recommend" → grammatically choose whomever.
- Many native speakers still use whoever in speech; in very formal writing "whomever" can be correct here.
- Give it to whoever asks. → "whoever asks" = subject of asks → whoever (not whomever).

Reduced (non-finite) relative clauses: when can I shorten a clause?

- You can often reduce a relative clause when the verb is passive (use past participle) or when using an -ing form for active meaning.

Past participle (reduced passive):
- Full: The letters that were sent yesterday arrived today.
- Reduced: The letters sent yesterday arrived today.

Present participle (active reduction):
- Full: The students who are taking the test must arrive early.
- Reduced: Students taking the test must arrive early.

To-infinitive reductions (common after adjectives, superlatives, or nouns indicating purpose):
- Full: She is the person who I want to invite.
- Reduced: She is the person to invite. (Note: meaning can change; use carefully.)

Cautions:
- Only reduce when the meaning stays clear. Some reductions can be ambiguous or ungrammatical if the subject is unclear.
- If the relative clause has its own subject different from the head noun, you usually cannot reduce it.
- The man who we saw leaving → The man we saw leaving (OK: "we" is subject of "saw")
- The man who left the room → *The man leaving the room? (This changes meaning; be careful.)

Prepositions: should I put the preposition before the relative pronoun or at the end?

Preposition fronting vs preposition stranding

- Two choices exist when a relative clause needs a preposition:
1. Front the preposition (more formal): the person to whom I spoke
2. Strand the preposition (more informal/natural speech): the person I spoke to

Examples:
- Formal (preposition fronted): The colleague with whom I worked moved away.
- Informal (preposition stranded): The colleague I worked with moved away.
- Formal: The city in which she was born is beautiful.
- Informal: The city she was born in is beautiful. (better: The city where she was born)

When to prefer fronting:
- In formal writing, especially when the preposition is long or the clause is long, fronting with whom/which is clearer.
- In speech and informal writing, preposition stranding is normal and idiomatic.

Use relative adverbs when simpler:
- where for place: The house where I grew up
- when for time: The year when we moved
- why for reason: The reason why he left

Restrictive vs non-restrictive: punctuation and meaning (again, with examples)

- Commas change meaning. Watch these minimal pairs:
- My friend who lives in London is an architect. (Restrictive: I have more than one friend; the one who lives in London is an architect.)
- My friend, who lives in London, is an architect. (Non-restrictive: I have one friend; additional info: she lives in London.)

- "That" cannot be used in non-restrictive clauses set off by commas:
- Correct: My car, which I bought last year, is red.
- Incorrect: My car, that I bought last year, is red.

Common mistakes and how to avoid them

- Using whom when who is required (subject position):
- Incorrect: The woman whom works here is kind. → Correct: The woman who works here is kind.

- Using who for objects in very formal writing where whom would be better:
- Informal OK: Who did you see? (= whom did you see?)
- Formal: Whom did you see?

- Confusing that and which:
- Restrictive (no commas): Use that (AmE preferred) or which (BrE): The phone that rings belongs to Tom.
- Non-restrictive (with commas): Use which: The phone, which rings loudly, belongs to Tom.

- Misplacing commas and changing meaning (see restrictive/non-restrictive examples above).

- Using whose only for people (not necessary): "Whose" is accepted with things in modern English: A city whose population is growing.

Practical tips:
- If unsure whether to use who or whom, try the he/him test.
- If a clause is long or formal, consider fronting the preposition and using whom/which.
- If a clause just gives extra information, set it off with commas and use which (for things) or who (for people).
- If a clause is essential, do not use commas and use that for things in American English.

Quick reference and glossary

- who: subject relative pronoun for people (The woman who called is here.)
- whom: object relative pronoun for people (The man whom you met is here.) — formal/after prepositions
- whose: possessive relative pronoun (The girl whose phone rang)
- which: relative pronoun for things or animals (The cup which was broken) and for non-restrictive clauses
- that: restrictive relative pronoun for things (and informally for people) (The book that I want)
- where/when/why: relative adverbs for place/time/reason (The place where we met)
- contact (omitted) relative: omit pronoun when it is an object (The book I read)
- reduced relative clause: use -ing, -ed, or to-infinitive to shorten (Students studying late…)
- fused/free relative: what, whoever, whatever (What I want is rest.)

Final tips:
- In spoken English, use who and allow preposition stranding; in formal writing, use whom after prepositions and consider fronting the preposition.
- Use commas for non-restrictive clauses and do not use "that" in them.
- When sentences become deeply nested and hard to follow, rewrite the sentence into two or more clearer sentences.

Comprehensive example set (summary):

- Restrictive (no commas): The students who study regularly pass. (essential)
- Non-restrictive (commas): My teacher, who loves jazz, is from New Orleans. (extra info)
- Who (subject): The man who called is outside.
- Whom (object): The man whom I called is outside. / The man I called is outside. (practical)
- Whose (possession): The woman whose car was hit is filing a report.
- Which (non-restrictive): The movie, which I saw last night, was excellent.
- That (restrictive): The movie that won the award is excellent.
- Preposition fronted (formal): The friend with whom I traveled is helpful.
- Preposition stranded (informal): The friend I traveled with is helpful.
- Reduced passive: Documents signed yesterday arrived.
- Reduced active (-ing): Students studying for exams should review notes.
- Fused relative: Whatever you decide will be fine.

Glossary

- Antecedent: the noun the relative clause modifies (the "head" noun).
- Relative pronoun: words that introduce relative clauses (who, whom, whose, which, that).
- Restrictive/defining clause: gives essential information to identify the noun.
- Non-restrictive/non-defining clause: gives extra information; set off with commas.
- Preposition stranding: leaving the preposition at the end ("the person I spoke to").
- Preposition fronting: placing the preposition before the relative pronoun ("the person to whom I spoke").
- Fused (free) relative: a clause that acts as a noun phrase without an antecedent ("what I need").
- Reduced relative clause: a shortened relative clause using participles or infinitives.

If you want, I can provide a shorter cheat sheet (one page) with only rules and quick examples, or I can rewrite complex example sentences into clearer alternatives for practice.