A Pro Guide to Using Which VS That

Short answer: In both British English and American English, that is used as a relative pronoun in a restrictive relative clause, whereas which is used as a relative pronoun in both restrictive and nonrestrictive relative clauses. 

This usage of the words in which vs that is governed by a grammar rule which will be discussed in the following portion of the article.  

 

It's an undeniable fact that the learners of English are at sea with the various uses of and grammar rules related to the words such as which vs that, who vs that, what vs that, whom vs that. 

This article has been designed to put an end to the confusions and doubts about the usage of the above-mentioned wh family words and relative pronouns.

This article covers:

• Which vs That - When to Use Them?
• Definitions of which, that, who, what and who
• Uses of which, that, who, what and who

 

WH Words with Uses and Examples

To completely abolish the doubts and confusions about which vs that, you need to be crystal clear about the basics of the wh words; that is, you must be familiar with the definitions and uses of and comparison among the words such as what, which, that, who, whom. 

Go through definitions, uses and examples of the following words with meticulous care so that not a single use of any of the above-mentioned words remains unclear to you.    

 

1. Uses of Which with Examples

Which is a wh-question word. We use which as a determiner or interrogative pronoun to seek specific information about someone, some place or something. 

We can also use which as a relative pronoun to introduce either defining or non-defining relative clauses.

 

a. Examples of which as a determiner in questions

1. Which book is yours?

2. Which pen are you buying?

3. Which room are you sitting in?

 

b. Examples of which as a pronoun in questions

1. Which do you like most? Tea or coffee?

2. Which do you prefer? Blue pen or black one?

3. Which is your favorite movie? The Titanic or the Romeo and Juliet?

  

c. Which as a relative pronoun in relative clause for animals and things 

1. The bird, which was sitting on the tree, flew away. 

2. The man spoke against the opposition party, which was liked by everyone.

3. The train which is leaving now will return tomorrow. 

d. Which for limited range of answers 

1. Which is the capital of India? Delhi or UP?

2. Which is the better one for tourists? Car or bus?

3. Which is the best movie? The Titanic, the Romeo and Juliet or the Camera?

2. Uses of That with Examples

That is used to render various functions in English grammar: as a determiner, as a demonstrative pronoun, as a relative pronoun and as a conjunction in that-clauses. 

a. Examples of that as a determiner

1. That car is mine.

2. That house is to let.

3. That movie is fantastic.

b. Examples of that as a demonstrative pronoun

1. That is my office.

2. That is his car.

3. Is that your pen?

 

c. Examples of that as a relative pronoun for people, animals and things 

1. This is the boy that met me yesterday.

2. This is the dog that was barking then.

3. The idea that occurred to me was to close the shop.

 

d. Examples of that as a conjunction in that-clauses

1. Are you sure that he will quit his job?

2. He confessed that he stole the watch.

3. He knew that he would be caught. 

3. Uses of Who with Examples 

Who is used as an interrogative pronoun or a relative pronoun to ask questions or add information about people.

a. Examples of who as an interrogative pronoun

1. Who is your father?

2. Who is the leader?

3. Who will win the game?

b. Examples of who as a relative pronoun 

1. The boy who was talking to you that time is my friend.

2. My son, who is 9, has topped the class.

3. This is the man who threatened me. 

 

4. Uses of Whom with Examples 

Whom is the object form of who. Whom is used mainly in two ways: as a question word and as a relative pronoun.

a. Examples of whom as a question word

1. Whom should I ask?

2. Whom did you tell?

3. To whom are you talking?

b. Examples of whom in relative clause 

1. The boy whom you met yesterday is my friend. 

2. The girl whom John married is Sofia's sister.

3. The man whom you saw at the library is my uncle.

5. Uses of What with Examples 

What is used as a determiner, pronoun and in exclamatory sentences. Here are a few examples of what.

a. Examples of what as a determiner 

1. What time will you go?

2. What books are you going to buy?

3. What time is it?

b. Examples of what as a pronoun 

1. What occurred to me was to wait.

2. What are you going to do?

3. I don't understand what he's saying.

c. Examples of what in exclamatory sentence 

1. What a lovely house it is!

2. What an idiot he is!

3. What a shame!

Also read: All wh question words

Now that you've learned the meanings, definitions and uses of the words, let me take you to the actual question: Which vs That - When to Use Them?

Which vs That - When to Use Them?

The relative pronouns such as which and that introduce relative clauses. The relative clauses introduced by these two pronouns can be of two types. They're given as under:

1. Restrictive or defining relative clause: a type of relative clause which, if removed, can destroy the meaning of the sentence; that is, removing the restrictive or defining relative clause makes the sentence meaningless.

For example:

• The book that contains a list of 1,000 English words is interesting. 

The highlighted phrase is a restrictive or defining relative clause and contains the relative pronoun that. If this relative clause is removed, the sentence will lose the actual meaning, because, when removed, the sentence will be "The book is interesting," which doesn't convey the fact that the book contains 1 thousand English words. 

2. Non-restrictive or non-defining relative: a type of relative clause which, if omitted from the sentence, cannot destroy the meaning of the sentence; that is, removing the non-restrictive or non-defining relative clause doesn't make the sentence meaningless.

For example:

• The book that contains a list of 1,000 English words, which I read everyday, is interesting.  

 

The highlighted phrase is a non-restrictive or non-defining relative clause and contains the relative pronoun which. If this highlighted relative clause is removed, the sentence will still be completely meaningful, because the highlighted relative clause simply adds additional meaning to the sentence. 

  

Uses of Which Vs That in Relative Clauses 

Which as a relative pronoun is used in both restrictive and non-restrictive clauses, whereas that as a relative pronoun is used only in restrictive relative clauses.

The main differences between which and that in relative clauses are: 

1. which is used for living and non-living things or objects, but not for people, whereas, that is used for living and non-living things, also for people. 

2. which is used in both restrictive and non-restrictive relative clauses, whereas that is used only in restrictive clauses. 

3. A non-restrictive relative clause with which is separated by commas, whereas, a restrictive relative clause with that is not.  

So, use which in both restrictive and non-restrictive relative clauses, and use that only in restrictive relative clause. 

Examples of Which in Restrictive Relative Clause

1. The book which deals with politics is boring.

2. The dog which bit you yesterday is here. 

3. The app which is used for online meeting is this.

Examples of Which in Non-restrictive Relative Clause

1. The book on English grammar, which I read everyday, is very interesting.

2. Your only white cat, which you feed everyday, is really cute. 

3. My laptop, which I purchased last year, performs very well. 

Examples of That in Restrictive Relative Clause

1. The boy that came to you yesterday is my brother.

2. The book that delves into the modern world politics is interesting. 

3. The woman that dressed in red is my aunt.