Adjective clauses and their types: essential and non-essential adjective clauses

In this post, we learn what an adjective clause is, and how to use it in English. At the end, a video lecture on adjective clauses is attached; you can directly scroll down to it if you prefer videos to articles.

What is an adjective clause?

An adjective clause is a type of a dependent clause that works as an adjective. It comes right after the noun or the pronoun it modifies. An adjective clause starts with the following subordinating conjunctions (relative pronouns):

• Who
• Whom
• Whose
• That
• Which
• Why
• Where
• When.

Examples:

• The guy who lives next to my house is a professional fighter.

“Who lives next to my house” is the adjective clause that’s coming next to the noun ‘guy’ and modifying it.

• I love the book that my father gifted me on my last birthday.

“That my father gifted me on my last birthday” is the adjective clause that’s sitting next to the noun book and modifying it.

• We haven’t been to Dubai, which is one of my dream places to visit.

“Which is one of my dream places to visit” is the adjective clause that’s sitting next to the noun ‘Dubai’ and giving information about it. But here, it is giving non-essential information about the noun it’s modifying and that is why it is offset using a comma. ‘Dubai’ is a proper name and doesn’t need any modification to be identified.

Types of adjective clauses in English

There are two types of adjective clauses based on the information they give:

• Essential adjective clauses
• Nonessential adjective clauses

Essential adjective clause

Essential adjective clauses are dependent clauses that modify a noun or a pronoun with essential or defining information. The noun or the pronoun they identify are not proper or specific. An essential adjective clause is important to the meaning of the sentence as it gives essential information about the noun or pronoun it modifies.

Examples:

• I don’t know anyone who can teach you boxing.
• People who can control their minds live a highly successful life.
• We are looking for a place where we party peacefully.
• I know the reason why she broke up with you.
• That was the year when we got married.
• The box that you sent me yesterday was empty.
• I still have the letter that she had written for me on Valentine’s day.

Try reading these sentences without the adjective clauses; the sentences will have a completely different meaning without them. That’s why we are calling them essential adjective clauses as they are essential to render the right meaning.

NOTE: Essential adjective clauses are also called defining adjective clauses.

Nonessential adjective clause

Nonessential adjective clauses are dependent clauses that modify a noun or a pronoun with nonessential or non-defining information. The noun or the pronoun they identify are proper (already identified), and that’s why they are offset using commas.

Nonessential adjective clauses are also called non defining adjective clauses.

Examples:

• Last month, we went on a trip to Auli, which is a beautiful place.
• Jon Jones, who is the light heavyweight champion in the UFC, got arrested last night.
• She doesn’t even know Max, whose bag she has stolen.
• Russell Peter, who is a famous comedian, is coming back to India after 15 years.
• After all the travelling and shopping, we dropped the plan to go to the Red Fort, which is a famous monument.
• Mangoes, which I love eating, are used in many dishes.

(Note that though ‘mangoes’ is a common noun, we are using commas before and after the adjective clause as it just passes a comment on them, not identify them or tell us which mangoes the speaker is talking about.)

Note that these adjective clauses are not essential to the core meaning of a sentence; they are just giving bonus information, which does make a sentence more attractive and meaningful, but they are not giving essential information about the nouns/pronouns they are modifying as they are already identified/specified.

How to form an adjective clause in English?

There are 3 components that you need in order to form an adjective clause in English:

1. Relative pronoun
2. The subject of the clause (noun or pronoun)
3. The verb of the subject

These are the 3 things you need, at least, to form an adjective clause in English. Also note that an adjective clause sits right next to a noun or a pronoun, generally a noun, and modifies it with some information.

The relative pronoun (conjunction) sometimes works as the subject of an adjective clause. Look at these examples carefully:

• The boy who was playing here yesterday has gone missing.
• We haven’t seen a man that can walk on water.

Adjective clauses and commas

Should adjective clauses be offset using commas or not? That depends on the job your adjective clause does in a sentence: if it gives essential (important) information to identify the noun/pronoun it modifies, don’t use commas to offset it. But if it gives extra information (non-essential) or just passes a comment on the noun or pronoun it modifies, not helping the readers to identify the noun/pronoun it modifies, use commas to offset it.

• I know a man who can teach you English. (Specifying which man the speaker is referring to)

• Virat Kohli, who is one of the best Indian cricketers, has opened an academy that will help school students to learn cricket.

This sentence has two adjective clauses: the first one “who is one of the best Indian cricketers” is giving extra or non-essential information about the proper noun ‘Virat Kohli’, but the second adjective clause “that will help school students to learn cricket” is modifying the noun ‘academy’ with essential information; it’s helping us understand what type of an academy it’s going to be.

NOTE: ‘Who’ can be used to give essential and nonessential information, and ‘which‘ can’t be used to give essential information.

We can omit the relative pronoun in some cases.

If a relative pronoun has the subject of the adjective clause, it can be taken out of the adjective clause without changing its meaning.

• She is the girl who I love.
• She is the girl I love.

• The match that we watched at his house was epic.
• The match we watched at his house was epic.

But if the relative pronoun itself works as the subject of the adjective clause, don’t omit it.

• He is the person who can get you out of this situation.
• He is the person can get you out of this situation. ❌

NOTE: relative adverbs (when, where, why) aren’t omitted even if they have their subjects.

• We can’t remember the year when we got married.
• We can’t remember the year we got married. ❌

• I know a place where we can hide the money.
• I know a place we can hide the money. ❌

• That’s the reason why nobody confides anything in you.
• That’s the reason nobody confides anything in you. ❌

WHO vs THAT

‘That‘ can be used in place of ‘who‘ in an adjective clause as that can be used to refer to both a person and a thing.

• The man who is standing next to Simran is a magician.
• The man that is standing next to Simran is a magician.

NOTE: when ‘that‘ is referring to a thing, ‘who‘ can’t be used in place of it. It is only possible when ‘that’ is referring to a person.

• Do you still have the mobile that your father gifted you in 2015?
• Do you still have the mobile who your father gifted you in 2015? ❌

• Talk to the girl that is wearing the red top.
• Talk to the girl who is wearing the red top.

More examples of adjectives clauses

• Do you have anything that I can read on the plane?
• The man whose daughter you have kidnapped is a gangster.
• Rajiv Chowk, which is one of the most famous metro stations in Delhi, is the place where I used to meet her.
• Do you still remember the time when we would bunk classes to play games?
• Most people don’t know the reason why they do what they do.
• The adjective clauses are colored red, and the nouns or pronouns they are modifying are in bold.

Key points

1. Both the relative pronouns WHO & THAT can be used in an essential adjective clause or a non-essential adjective clause.

• Arijit Singh, who is a brilliant singer, is from my hometown.
• Titanic, which is my favorite movie, was shot in a swimming pool.

• The boy who was selling notebooks at the stand was homeless.
• The book that is on the table is amazing.

2. The relative pronoun ‘THAT‘ can refer to both a person and a thing.

• I lost the card that she had given me. (referring to a thing)
• I know the girl that you are dating these days. (referring to a person)

3. An adjective clause is a dependent clause. It can’t stand on its own.

Adjective clauses are a type of a dependent clause. It doesn’t give complete meaning on its own. It must be added to an independent clause to render a complete meaning.

• Who loves you. (incomplete sentence, adjective clause)
• I know someone who loves you. (complete sentence)