Mastering the Difference Between the Usage of Which vs. That 

You must have used which vs. that a thousand times in your research till now. In fact, we all use the two words very frequently in our day to day writing. But the commonality of these words doesn’t guarantee their ease of use. They cause a lot of confusion at times, and questions like, ‘Can we use which vs. that’, interchangeably?‘ Is there really a difference between the usage of which vs. that?,’ come up almost every time in our heads.  

So here’s a blog, explaining the right usage of the two words and attempting to bring all confusion to rest. 

When to use which vs. that

To determine when to use which vs. that, you will need to understand the difference between restrictive and non-restrictive clauses.  

A non-restrictive clause (often also called a non-essential or non-defining clause) provides extra information about a noun. It can be removed from a sentence without changing its meaning, so, when a non-restrictive clause is removed, the sentence will be grammatically complete and will make sense on its own.  

A restrictive clause (also called an essential or defining clause) functions like an adjective in a sentence to specify which of several similar things is being indicated. It describes and sets limits on a noun.  

So, when the information provided by the clause is essential to the sentence’s meaning, you use that. If the information provided by the clause is additional but not essential, you use which. 

Pro Tip: Remember that non-restrictive clauses are set off by commas, while restrictive clauses are not. This helps in differentiating between the two and ensures that you are not confused when to use which vs. that.  

Learn using which vs. that with examples

As we saw above, which is a pronoun used to provide additional information about a noun but is not necessary for the sentence’s meaning.  

For example, “The thesis, which was written by Jade, was interesting.”

In this sentence, the clause “which was written by Jade” is a non-restrictive clause that provides additional information about the thesis. Here, the fact that the thesis was written by Jade is simply a description of the thesis, and the sentence would be complete even without it.  

That is used to provide essential information about a noun and is necessary for the sentence’s meaning. For example,  

“The thesis that was written by Jade was interesting.”

In this sentence, the clause “that was written by Jade” is a restrictive clause that is essential for the sentence’s meaning. It tells us specifically that the reader found the thesis written by Jade (and not just any other thesis), interesting. 

Which vs. that examples

“The greatest discoveries of science have always been those that forced us to rethink our beliefs about the universe.” – Lawrence M. Krauss, American theoretical physicist and cosmologist. 

“The highest form of intelligence is to observe things without preconceptions and to understand things which cannot be seen.” – Jiddu Krishnamurti, Indian philosopher and writer. 

“The most exciting phrase to hear in science, the one that heralds new discoveries, is not ‘Eureka!’ (I found it!) but ‘That’s funny …'” – Isaac Asimov, Russian-born American biochemist and science fiction writer. 

In conclusion

We hope the article brings out the difference between the usage of which vs. that clearly and helps you write grammatically correct research. We also have some articles explaining insure vs.ensure, too vs. too, inter vs.intra and many other similar sounding words, so check them out too!