Which Vs That: A Comprehensive Guide

For many writers, knowing the difference between which vs that can really trip them up. This guide will help set the record straight. 

The words “that” and “which” are problematic for English writers because they carry similar meanings. Yet strong writers will know when to use each of these words, and how to use commas appropriately with them, to make the meaning of the sentence clear.

[ninja_tables id=”55297″]

Which vs That: Similar but Different

“Which” and “that” are relative pronouns used to introduce clauses modifying nouns. “That” introduces restrictive clauses—essential information that defines the noun—while “which” introduces non-restrictive clauses, set off by commas, that add optional detail. According to the Cambridge Dictionary, relative pronouns introduce dependent phrases that cannot stand alone.

Both that and which are relative pronouns. The Cambridge Dictionary defines relative pronouns as pronouns that introduce relative clauses. A relative clause is a dependent phrase with a subject and verb that cannot stand alone.

Both of these terms tell the reader to look closely at the information provided. They indicate additional information that gives a better meaning to another part of the sentence. These could be called, “defining clauses” because they define another part of the sentence.

In addition, these words can get used as adjectives, pronouns, conjunctions or adverbs. However, the most common use is as a relative pronoun.

These words are easy to confuse because they look similar in the sentence structure, but a closer look at the grammar shows they are not the same.

Restrictive vs Non-Restrictive Phrases

The key to understanding how to use “that” and “which” appropriately is understanding the difference between restrictive and non-restrictive clauses.This type of clause is necessary for the meaning of the sentence to be accurate.

This is an example of a sentence with a restrictive clause:

• The mom’s necklace that was made from macaroni noodles was a treasured keepsake.

In this sentence, the information about the necklace being made from macaroni is vital to the meaning of the sentence. It tells the reader that the mom’s child made the necklace, which is why it was a treasured keepsake. This makes it restrictive.

A nonrestrictive clause does not add meaning and is not necessary for the sentence. This would include:

• The mom’s necklace, which matched her blue dress, was a treasured keepsake.

In this sentence, the color of the necklace and dress is not vital to understanding the sentence’s meaning, and thus the phrase is non-restrictive.

Use “That” for Restrictive Clauses

English writers should use “that” when writing clauses that are restrictive. The use of “that” indicates the information in the clause is needed to understand the noun, or antecedent, that comes before. Here are some examples:

• My dog that I adore ate my shoe.
• The cashier that sold me the dress said it was returnable.
• The sweater that my mother gave me on my birthday got torn.

In the first example, the information about adoring the dog makes the sentence mean more, because it shows that the writer is not going to be too angry. In the second, knowing it was the same cashier that sold the dress giving the information about returns is important.

Finally, in the sweater example, the information differentiates between the writer’s other sweaters.

Use “Which” for Non-Restrictive Clauses

On the other hand, “which” is the term used for a non-restrictive relative clause. If the clause is not fully necessary to make the meaning of the sentence clear, it is set off by a comma and “which.” Here are some examples:

• We were late because of my daughter’s nap, which is fine because she needed it.
• The car, which parked next to me, was a brilliant red shade.
• The cloud made the child cry, which surprised the boy’s mother.

In each of these, the main meaning of the sentence does not change with the addition of the clause, so “which” is the appropriate pronoun.

The Comma Trick

Commas can help you when it comes to “which” and “that.” If you are using “that” and presenting important information in a restrictive clause, then you do not set off the clause with commas.

However, when presenting extra information with “which” in a nonrestrictive clause, you do set the clause off with commas. This shows that the clause is not vital to the rest of the sentence.

Sometimes the clause could even be a second sentence separate from the original one.

The Final Word on Which vs That

Because they are both relative pronouns that set off clauses, “that” and “which” can trip up writers. To choose the right word, always determine if the clause is necessary to the meaning of the sentence, in which case you use “that” and no commas. If it is not, then you use “which” with commas.

It really is that simple to learn the difference between which vs that. If you liked this post, you might also be interested in our gone vs. went guide.

FAQs About Which vs That

---

Frequently Asked Questions

What is the difference between ‘which’ and ‘that’ in English grammar?

“That” introduces a restrictive clause, meaning the information is essential to the sentence’s meaning and cannot be removed. “Which” introduces a non-restrictive clause, providing optional extra detail that is set off by commas. For example: ‘The car that won the race was red’ (restrictive) vs. ‘The car, which was red, won the race’ (non-restrictive).

When should you use ‘that’ in a sentence?

Use ‘that’ when the clause following it is essential to identifying the noun it modifies. Without the ‘that’ clause, the sentence’s meaning would be incomplete or ambiguous. For example, ‘The report that the manager submitted was approved’ specifies which report, making the clause restrictive and necessary.

When should you use ‘which’ in a sentence?

Use ‘which’ when introducing a non-restrictive clause—additional information that adds context but is not required to understand the sentence. Non-restrictive clauses are enclosed in commas. For example, ‘The report, which was submitted on Monday, was approved’ uses ‘which’ because removing the clause does not change the core meaning.

How do commas work with ‘which’ and ‘that’?

Commas are used with ‘which’ because it introduces non-restrictive clauses that function as parenthetical additions to the sentence. ‘That’ clauses are restrictive and do not require commas. A simple rule: if you can remove the clause without changing the sentence’s main meaning, use ‘which’ and add commas.

Are ‘which’ and ‘that’ interchangeable in American English?

In American English, ‘which’ and ‘that’ are not interchangeable in formal writing. The Chicago Manual of Style and most U.S. style guides distinguish ‘that’ for restrictive clauses and ‘which’ for non-restrictive clauses. British English is more flexible, occasionally allowing ‘which’ in restrictive clauses, but clarity is best served by following the American convention.