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Ch 8

Relative Clauses

Defining · non-defining · omission

Defining vs non-defining

At B1, you learn the difference between clauses that define a noun (essential) and clauses that add extra information (non-essential).

Defining (no commas)
The student who passed the exam got a prize. (tells us which student)
Non-defining (commas)
Maria, who passed the exam, got a prize. (we already know it's Maria)
In non-defining clauses, that cannot replace who or which. Also, you cannot omit the pronoun.

Defining clauses: omitting the pronoun

When the relative pronoun is the OBJECT, it can be removed

Pronoun as subject
The man who called was polite. (cannot omit — who is the subject)
Pronoun as object
The book (that) I read was brilliant. (can omit — that is the object)
Can omit (object)
The film [that] I watched was great.
The woman [who] I met was friendly.
Cannot omit (subject)
The man who called me. ✓
The dog that bit him. ✓

whose · where · when

whose (possession)
The scientist whose research changed medicine won the prize.
where (place)
The hotel where we stayed was excellent.
when (time)
I remember the day when we first met.
A mechanic is someone whose job is to fix cars.
2008 was the year when the crisis started.

Non-defining: extra information

Commas signal that the clause is additional, not essential

Non-defining with who
My sister, who lives in London, is a doctor.
Non-defining with which
The report, which was published last week, was controversial.
Never "that" in non-defining
✗ My sister, that lives in London, is a doctor.
Test: remove the clause. If the sentence still makes sense AND the noun is already identified → non-defining (use commas).

Common mistakes

My father, that is a doctor, works long hours.
→
My father, who is a doctor, works long hours.
non-defining → never "that"
The book which I read it was great.
→
The book which I read was great.
don't repeat the pronoun (it)
The company where I work in is small.
→
The company where I work is small.
no preposition after where
She is the person who her book I read.
→
She is the person whose book I read.
possession → whose

Recap

Defining
no commas · tells us which one
The man who called was friendly.
Non-defining
commas · adds extra info · no "that"
Maria, who is my sister, called.
Omit pronoun
only when pronoun = object of clause
The film (that) I watched
whose/where/when
possession · place · time
whose book / where I worked
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