Complements: What Are Complements? Definition and Types (Examples)

You see complements all the time in English sentences, but do you know what they are? And if you had to find one, would you know what you're looking for? If the answer is 'no,' don't worry. Once you've read this article, you'll know exactly what a complement is and the purpose they serve in English grammar.

In short:

• A complement gives additional information about either the subject or the object of the sentence.

This guide is part of our free online Grammar Book.

What Are Complements?

In grammar, complements serve to complete the meaning of a sentence by giving additional information. Complements aren't optional, unlike modifiers or adjuncts. They are essential to the meaning of the sentence and, if removed, would render it meaningless.

Complements can be a single word, a phrase, or a clause, and can be one of two major types:

• Subject complements
• Object complements

Subject Complements

A subject complement is:

• Noun, pronoun, or adjective (or phrase or clause that functions as one of these three)

It provides additional information about the subject. It does that either by renaming or describing.

It always follows a linking verb.

Here's an example of a noun functioning as a subject complement:

My husband is a doctor.

Let's break this down a little. The subject is 'husband,' and as we've learned, the subject complement serves to add information about the subject. 'Doctor' gives more information about the subject 'husband' by telling us what his job is. Therefore, 'doctor' is the subject complement. Notice how it follows the linking verb 'is.'

This kind of subject complement - the kind that's a noun - is also called a predicate nominative. This also includes pronoun subject complements, like 'her' in the following sentence:

Look, it's her!

Now here's an example of an adjective functioning as a subject complement:

Your shirt looks new.

The subject is 'shirt,' and the adjective that complements it is 'new.' Therefore, 'new' is the subject complement. Again, notice it follows a linking verb 'looks.'

This kind of subject complement - the kind that's an adjective - is also called a predicate adjective.

Object Complements

An object complement is:

• A noun, pronoun, or adjective.

If subject complements tell us more about the subject, then you might have guessed that object complements tell us more about... the object. The direct object, specifically.

They always come straight after the direct object in a sentence.

Here's an example of an object complement:

That story made me sad.

The object complement here is the adjective 'sad.' How do we know? Well, first of all, let's find the direct object. To do that, we ask, "To what/whom is the verb being done?". The verb here is 'made.' Who is being made? 'Me.' Therefore the direct object is 'me.' 'Sad' describes 'me,' making it the object complement. Plus, it's directly after the direct object 'me,' so that's another clue.

Here's another example, this time with a noun as an object complement.

They elected him president for the fourth year in a row.

And here's one more example with a pronoun as an object complement.

You'll need to speak to the boss: me.

Now here's something cool. Look at these two almost identical sentences:

The dog was stupid.

I found the dog stupid.

'Stupid' in the first sentence is a subject complement because 'dog' is the subject, and it is the dog that is stupid. Your other clue is that 'stupid' follows the linking verb 'was.'

'Stupid' in the second sentence, however, is an object complement because 'dog' is now the object ('I' is the subject), and it is still the dog that's stupid (sorry, dog, I'm sure you're awesome!).

Other Meanings for Complements

The thing about grammar is it isn't always one-size-fits-all. I know, weird, right? You'd think they'd make one set of rules and have everyone stick to them. Unfortunately for us, that's not the case. Or, maybe, fortunately. After all, it does keep things interesting and flexible, and it means we can often make something mean what we want it to mean. Plus, rules are boring, right?

I wanted to mention this because you will see other meanings for the word 'complement' floating around, and I don't want you to be confused. Those definitions are legitimate, as are the ones described in this article.

Examples in a Sentence

That pretty much covers it in terms of complements and what they are. What I'm going to do now is give you some more examples of the two kinds to make sure that it's perfectly clear in your mind.

Examples of Subject Complements

The new house is a work in progress.

Angela seemed quite nice.

All I want is to make you happy.

This place smells like rotten fish.

Revenge is a dish best served cold.

Examples of Object Complements

I caught her spying on us.

We're going to paint the town red.

I just want to make you happy.

I found him working on his essay.

They named the baby Johnny.

Concluding Thoughts

That concludes this article on complements. I hope you found it helpful and that you feel confident you can go out and master complements, as well as use them appropriately in your sentences.

Let's summarize what we've learned:

• Complements come in two forms: subject complements and object complements.
• Subject complements give information about the subject and always follow a linking verb.
• Object complements give information about the object and always follow the direct object. 

If you found this article helpful and would like to learn about even more grammar concepts, head to our Grammar Book, an online database full of free English Grammar articles.