What are gerunds?

Gerunds are words that are formed from verbs but act as nounsYou'll be able to spot them because they will be a verb + ing acting as a noun.

Swimming is fun.

The word swim is a verb. Swimming is a verb with an -ing ending acting as a noun. It is the subject of this sentence.

Tip: Words that are formed from verbs but don't act as verbs are called verbals. There are two other types of verbals: participles and infinitives.

What is a gerund? Learn here!

They can do anything that nouns can do. That means that they can be subjects, direct objects, objects of prepositions, predicate nouns, and more!


These consist of a gerund and the words that modify and complement it.

Swimming in the pool is fun.



Running is my favorite activity.
Running marathons is
my favorite activity.
I love listening.
I love listening to my favorite band.
Reading rocks!
Reading books on the porch rocks!

Modifiers & Complements


You remember what these act as NOUNS, right? Of course you do.

You also remember that nouns are modified by adjectives, right? If you aren't comfortable with that yet, you should probably be reading up on the eight parts of speech.

Adjectives and adverbs are called modifiers because they modify (describe) other words.

Okay, let's get back to the matter at hand. Let's look at one of those examples from above.

Swimming in the pool is fun.

You may have noticed that in the pool is an adverbial prepositional phrase. It is telling us where the swimming happened.

(Where is one of the adverb questions.)

You should now be saying to yourself, "Hey! Nouns can only be modified by adjectives. What gives, Elizabeth?"

Here is what gives. ---> Gerunds are formed from verbs.

Even though they are officially nouns, they still carry some of the attributes of verbs.

Their "verbness" allows these guys to take adverbial modifiers just like any other verb - even though they act as nouns. (By the way, they can still take adjectival modifiers just like other nouns.)

Gerunds can even do other verby things...


Complements are things like direct objects. They complete verbs.

Guess what?

These babies can have complements!

Running marathons is my favorite activity.

Marathons is the direct object of running.


Are you ready to hear something kind of strange? They can even have subjects... sort of.

Subjects are usually in the subject case (I, he, she), but these subjects will always be in the possessive case (his, her, my).

His snoring keeps me awake.

His is the "subject" of snoring.

In a Sentence...

Acting As...

Its Complement/Modifier...

Diagramming sentences is fun! Subject Sentences is the direct object of diagramming.
I love listening to my favorite band. Direct Object To my favorite band is a prepositional phrase modifying listening.
Mary's loud eating really bothers me! Subject Mary's is the "subject" of eating.
Loud is an adverb modifying eating.

Basic Sentence Diagramming

These sit on steps when you diagram them.

The verb part goes on the top part of the step, and on the -ing goes on the bottom part of the step.

After that, you diagram the modifiers and complements just as you would with any other word.

Other Helpful Resources

Elizabeth O’Brien is the creator of Grammar Revolution, an online business dedicated to making grammar easy to teach and fun to learn. Once a typical K-12 student fearful of grammar, Elizabeth has become a grammar lover thanks to the forgotten art of sentence diagramming, an art she is now breathing fresh life into.

After earning a B.S. degree in Elementary Education at the University of Wisconsin – Eau Claire, she spent four years teaching grammar, literature, and writing. Since 2009, she’s been developing grammar programs and leading social media communities as part of her mission to revive grammar instruction.

Grammar Revolution provides step-by-step grammar and sentence diagramming materials to teachers, schools, and homeschoolers around the world.

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