Relative Clauses ( Defining or Non-defining Relative Clauses?)

What is RELATIVE CLAUSES??
We can use relative clauses to join two English sentences, or to give more information about something.
I bought a new bike. It is very expensive.
→ I bought a new bike that is very expensive.
I live in Houston. I like living in Houston.
→ I live in Houston, which I like.

Relative Clauses are divided into two types : 1. Defining and ; 2. Non-defining

Now, let's find out what are they :
A defining relative clause tells which noun we are talking about:

• I like the woman who lives next door.
  (If I don’t say ‘who lives next door’, then we don’t know which woman I mean)

A non-defining relative clause gives us extra information about something. We don’t need this information to understand the sentence.

• I live in Jakarta, which has some fantastic tourism spots.
  (Everybody knows where Jakarta is, ‘which has some fantastic tourism spots’ is extra information)

Defining relative clauses:

1: The relative pronoun is the subject:
First, let’s consider when the relative pronoun is the subject of a defining relative clause.
We can use ‘who’, ‘which’ or ‘that’. We use ‘who’ for people and ‘which’ for things. We can use ‘that’ for people or things.
The relative clause can come after the subject or the object of the sentence. We can’t drop the relative pronoun.
For example (clause after the object of the sentence): .

• She has a son who / that is a petroleum engineer.
• We bought a house which / that is 100 years old.

More examples (clause after the subject of the sentence):

• The people who / that live on the island are very friendly.
• The house which / that belongs to Jenny is in Bali.

2: The relative pronoun is the object:
Next, let’s talk about when the relative pronoun is the object of the clause. In this case we can drop the relative pronoun if we want to. Again, the clause can come after the subject or the object of the sentence. Here are some examples:
(clause after the object)

• She loves the nightgown (which / that) I bought.
• Jill met a woman (who / that) I had been to school with.

(clause after the subject)

• The bike (which / that) I loved was stolen.
• The woman (who / that) my brother loves is from Medan.

Non-defining relative clauses:

Remember, we don’t use ‘that’ in non-defining relative clauses, so we need to use ‘which’ if the pronoun refers to a thing, and ‘who’ if it refers to a person. We can’t drop the relative pronoun in this kind of clause, even if the relative pronoun is the subject of the clause.
(clause comes after the subject)

• My sister, who I live with, knows a lot about English.
• My mother's house, which I grew up in, is very small

(clause comes after the object)

• Yesterday I called our friend Julie, who lives in Texas.
• I really love the new Sunda restaurant, which we went to last night.

Non-defining relative clauses are more often used in written English than in spoken English. You can tell that a clause is non-defining because it is separated by commas at each end of the clause.