2. D.O. We are waiting for Apu. Apu is from India. Subj
Same thing in different sentences.
Apu is from India.

3. We are waiting for Apu,
who
India.
is from
Apu is from India.
Subj

4. We are waiting for Apu, who is from India.
The two sentences can be linked into one.
We use a relative pronoun to substitute the common item and join the two sentences in one.
We are waiting for Apu ,
who
is from
India.
This is the main clause.
This is the subordinate clause.
We are waiting for Apu, who is from India.
Subordinate/Dependent clause
Its meaning is incomplete if we remove the main clause.
Main /independent clause
If we remove the subordinate clause from the sentence, its meaning is still complete.

5. LINKING WORDS

6. LINKING WORDS

7. Two types of relative clauses:
Non-Defining
Extra information about a noun in a sentence
The new Woody Allen film, which I saw last week, is very good.
Use commas
Always use a relative pronoun:
who/whom ,which whose, where, when
Defining
Essential information about a noun in a sentence
You’re the man (that) I saw last week.
No commas
Can omit pronoun if it is not the SUBJECT of the relative clause
That (informal) can replace which / who/ when / why but not where, whose or whom

8. Defining relative clauses = No commas
A defining relative clause identifies which person or thing we mean exactly.
It cannot be left out of the sentence or the meaning of the sentence is incomplete:
It’s the book that I read yesterday.
* It’s the book. (this sentence is incomplete)

9. Defining relative clauses = No commas
You can omit the pronoun if it is the OBJECT of the relative clause (if there is a SUBJECT and a VERB after the relative pronoun )
It’s the book that I read yesterday (omit)
It’s the book I read yesterday.
The girl who lives next door is French.
We can never omit WHOSE and WHERE

10. Non-defining relative clauses = with commas
This kind of clause gives additional information about a person or thing.
The sentence still makes sense without the non-defining relative clause:
My neighbour, who studies engineering, is very noisy.
My neighbour is very noisy.

11. Formal / Informal
Non-Defining relative clauses (with commas) are more common in written English because they are quite formal.
In spoken English we would probably use two sentences.
Compare:
Elvis Presley, who has sold over one billion albums, died of prescription drug abuse. [written]
with
Elvis has sold over a billion albums. He died of an overdose. [spoken]

12. Verb + preposition
When the verb is followed by a preposition in the relative clause we can use two structures:
The woman is a lawyer. I spoke to a woman
Formal: Preposition + rel.pronoun
The woman to whom* I spoke is a lawyer.
(*We can’t omit the relative pronoun after a preposition) Or
Informal: Preposition after the verb
The woman (who) I spoke to is a lawyer.

13. Relative Adverbs Time: when or in/on/at + which or that
That was the year when/that/in which I got my degree.
11 September 2001 was the day when/that/on which people’s attitude towards terrorism changed.
The adverb (when) can be omitted.
11 September 2001 was the day people’s attitude towards terrorism changed.

14. Relative Adverbs Place: where or
in/on/at + which or that
That’s the factory where/in which they make chemicals.
That’s the spot where/on which the battle took place.
The adverb (where) cannot generally be omitted.

15. Relative Adverbs: Reason: why (for which)
I will explain the reasons why /for which the accident occurred
The adverb (why) can be omitted.
I will explain the reasons the accident occurred

16. Relative pronouns Possessive: whose
It takes the place of his, her, their or a noun in possessive case ‘s.
Andy Warhol was a pop artist whose paintings are famous worldwide.(His paintings are famous…)
Charlie, whose sister lives in London,
is travelling to England this summer. (Charlie’s sister lives in London).