Written by David S. Wills · July 10, 2023
In this lesson, I will explain the difference between essential and non-essential relative clauses in a way that is easy to understand. This will help make your writing clearer and more accurate.
What is a relative clause?
A relative clause is a clause that gives more information about a noun. It will begin with a relative pronoun, which is why it is known by that name. Relative clauses cannot function as complete sentences but they are useful for giving extra information.
Here is an example of a relative clause:
I bought the computer that I told you about.
Here, the relative clause “that I told you about” gives us more information about the noun, “computer.” This is an essential relative clause because the first part of the sentence does not make any sense without it. (We’ll discuss that more later.)
Important things to know about relative clauses:
- They come after the noun (which is known as an “antecedent”)
- A relative pronoun such as “that,” “which,” or “who” will come at the start
- They cannot function as a full sentence
- They may be essential or non-essential
What is an essential relative clause?
An essential relative clause is one that is essential for understanding the clause before it. In other words, the previous clause (and specifically the noun) does not have a definite meaning without the relative clause.
Let’s go back to our previous example:
I bought the computer that I told you about.
This is an essential relative clause because without it the previous part (“I bought the computer”) has no real meaning.
Imagine your friend said to you, “I bought the computer.” Without further context, this would be confusing. You would ask, “What computer?”
As such, people tend to add essential relative clauses to give more information. For example:
- I bought the computer that you recommended.
- I bought the computer that your brother told me about.
By adding more information,