GRAMMAR & STRUCTURE
When do we use "who" insted of "which"?
"Who" refers to people, "which" refers to things/animals.
Join the sentences:
This is the book. I told you about it.
This is the book (that/which) I told you about.
Add commas:
My brother who lives in Madrid is a lawyer.
My brother, who lives in Madrid, is a lawyer.
Fill in:
The woman ___ won the prize is my teacher.
who
Can we omit the pronoun? The book (that) you lent me is great.
Yes, if the pronoun is the object. Not when it's the subject
Is this defining or non-defining?
My dog, which is a Labrador, loves to swim.
Non-defining
Why is this sentence wrong? The teacher which gave the lecture is famous.
"Which" cannot refer to people; use "who" or "that".
Correct: The teacher who/that gave the lecture...
Rule: Who/that → people | Which/that → things/animals.
Correct the mistake:
The man which lives next door is a doctor.
The man who lives next door...
Replace with a relative clause:
Paris is the capital of France. It is famous for the Eiffel Tower.
Paris, which is the capital of France, is famous...
Choose a relative pronoun:
This is the house ___ I was born.
where
Rewrite:
The man who is talking to Sarah is my uncle.
The man talking to Sarah is my uncle.
Combine:
The keys were on the table. You were looking for them.
The keys (that/which) you were looking for were on the table.
Can we use "that" in non-defining clauses?
Example: My laptop, that is new, works well.
No, only in defining clauses (without commas).
Why can't we use "that" in non-defining clauses?
Historical Grammar Rule: In English, "that" has always been a pronoun restricted to essential clauses (defining). Non-defining clauses require "which" (for things) or "who" (for people) to clearly mark them as optional/extra information.
Contrasted Example:
✅ My car, which is red, is parked outside. (✔️ Correct – non-defining)
❌ My car, that is red, is parked outside. (✖️ Sounds unnatural to native speakers)
Logical Reason: The commas already signal that the information is "extra." Using "that" (which usually introduces critical information) would create confusion.
Complete:
The restaurant ___ we had dinner was expensive.
where
Correct:
The movie, that we saw yesterday, was boring.
The movie, which we saw yesterday, was boring.
Do not use that with commas. Only for critical information.
Defining: The books that are on the table are mine. (Only those books)
Non-defining: These books, which are on the table, are mine. (All books + extra info)
Which pronoun is unnecessary?
The dress that she bought it was expensive.
It
Correct:
The car which it is parked outside is mine.
The car which is parked outside is mine.
Correct:
The hotel where we stayed there was luxurious
Eliminate: THERE
When can we omit the relative pronoun (who/which/that)?
Example: The movie (that) we watched was exciting.
When the pronoun is the object (not the subject).
✅ Omitted: The dress (that) she bought was expensive. ("she" = subject, "that" = object → optional).
❌ Not omitted: The woman who called me... ("who" = subject → mandatory).
Transform:
She’s the singer. Her last album was a hit.
She’s the singer whose last album was a hit.
Combine:
Shakespeare wrote Hamlet. He died in 1616.
Shakespeare, who wrote Hamlet, died in 1616.
Complete:
The person ___ wallet was stolen called the police.
whose
Omit if possible:
The movie (that) we watched was scary.
The movie we watched...
Transform:
I have a friend. Her brother is a famous actor.
I have a friend whose brother is a famous actor.
Why do we use "whose" in:
The author whose books are famous lives here.?
It shows possession (= his/her/their)
Whose replaces possessive pronouns in relative clauses:
Original: The author. His books are famous. → Relative clause: The author whose books....
✖️ Don’t confuse with "who’s" (= who is).
Explain the difference:
"The students who passed the exam celebrated." vs. "The students, who passed the exam, celebrated."
"The students who passed the exam celebrated." DEFINING, ONLY SOME PASSED (THOSE CELEBRATED) NO COMMAS
"The students, who passed the exam, celebrated." NON-DEFINING, ALL PASSED (ALL CELEBRATED) WITH COMMAS
Explain why we CAN’T use "that" in non-defining clauses.
In English, "that" has always been a pronoun restricted to essential clauses (defining). Non-defining clauses require "which" (for things) or "who" (for people) to clearly mark them as optional/extra information.
✅ My car, which is red, is parked outside. (✔️ Correct – non-defining)
❌ My car, that is red, is parked outside. (✖️ Sounds unnatural to native speakers)
Logical Reason: The commas already signal that the information is "extra." Using "that" (which usually introduces critical information) would create confusion.
Explain when we can omit who/which/that in relative clauses.
You can omit who/which/that only when they are the object of the relative clause (not the subject).
✅ The book (that) you lent me is great. (✔️ "that" = object → can omit)
❌ The woman who called me is outside. (✖️ "who" = subject → can’t omit)
Rule:
Omit: If the pronoun is not doing the action (you lent the book).
Keep: If the pronoun is doing the action (who called).
Explain why we CAN’T omit the pronoun in:
The woman who lives here is a doctor.
Who is the subject. The one doing the action.
Create a sentence with "whom" in a formal context.
The scientist, whom we interviewed yesterday, discovered a new vaccine." FORMAL CONTEXT
Why "whom"? It’s the object of "interviewed" (we interviewed whom).
Less formal alternative: "The scientist (who) we interviewed..."