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Prepositions are one of the eight parts of speech in the English language, and they’re pretty important. Prepositions allow us to create complex sentences and add in important details. They play a crucial role in helping sentences make sense, which is super important when you need to communicate clearly and effectively.

But if you have to sit down and give an accurate preposition definition, things can get a little tricky. You may know that prepositions are usually short words like at, for, in, on, or under, but what is a preposition as a part of speech? What do prepositions do, and how the heck do you identify a preposition in a sentence?

To help you become an expert on prepositions, we’re going to talk about the following in this article:

• Answer the questions “What is a preposition?” and “What does preposition mean?”
• Explain each type of preposition definition with examples of each type used in a sentence
• Provide a list of four top tips for identifying prepositions in sentences

If there’s a specific type of preposition you want to know more about—like prepositions of space—you can find the information quickly by holding Command + F on your keyboard, then typing in the term you’re looking for.

Now without further ado, let’s get started!

Feature Image: (Jmayereup / Wikimedia)

What’s a Preposition? Preposition Meaning and Usage in Sentences

Grammar rules for the English language state that prepositions are defined based on their function in a sentence. So, here’s how a preposition functions to create meaning in a sentence: A preposition combines with a noun, noun phrase, or pronoun to demonstrate a relationship between the noun and another component of the sentence, often another noun and verb.

In other words, prepositions help readers understand the relationship between different nouns and verbs in a single sentence. 

Now that you’ve got an answer to the question, “What’s a preposition?” you’re probably wondering what kind of relationships prepositions show. Prepositions can show relationships of time, space, or possession between a subject and an object in a sentence. 

For example, in the following sentences, each preposition (in bold) helps us better understand the relationship between the cat and the table:

In the examples above, the prepositions on, under, beside, and at help clarify the nature of the relationship between the cat—the subject of the sentence—and the table—the object of the preposition. Notice that each sentence makes us visualize something different: a cat sitting on a table is not the same thing as a cat sitting under a table. And guess what? That’s what prepositions are designed to do! 

Here's a helpful list of prepositional phrases! 

The Prepositional Phrase 

The next thing you need to know about prepositions in sentences is that they almost always appear in a prepositional phrase. Prepositional phrases are important for communicating what types of actions and interactions occur between the subjects and objects of sentences. 

A prepositional phrase consists of a preposition (or prepositions), the object of the preposition (a noun, noun phrase, or pronoun), and any other words that modify the object (an adjective or adverb). In the examples above involving the cat and the table, on the table, under the table, beside the table, and at the table are all prepositional phrases because they begin with a preposition that is followed by a noun (cat).

Quick note: if you’re not sure what things like nouns, adjectives, or adverbs are, don’t worry. We have a complete, expert guide to each part of speech that will teach you everything you need to know!

Keep in mind that prepositional phrases aren’t limited to a single preposition and a single object. Prepositional phrases can also contain modifiers of the object, which are usually adjectives and adverbs. Here’s an example of a prepositional phrase that also contains modifiers: 

The cat sat under the dirty, decaying table. 

In this example, under the dirty, decaying table is the entire prepositional phrase. It consists of the preposition (under), the object (the table), and the adjectives that modify the object (dirty, decaying). So while a prepositional phrase must contain at least one preposition and an object, it can also contain other types of words. 

Now if someone asks you, “What is a preposition?” you have an answer! Next, we’ll break down the different types of prepositions for you so you’ll be a preposition expert. 

2 Forms of Prepositions and Prepositional Phrases You Need to Know

Part of answering the question, “What is a preposition?” includes explaining the two different forms, or structures, that prepositions and prepositional phrases can take. Think of form like a formula: it’s a prescribed way that you can put different prepositional words together to make them work in a sentence! 

Let’s look at the two forms of prepositions below.  

#1: Simple Prepositions

Simple prepositions are the first type of preposition, and it’s one of the two types that Defining simple prepositions is, well, simple: simple prepositions are one-word prepositions that appear at the beginning of a prepositional phrase in front of an object or in front of an article and an object. In other words, simple prepositions look something like this: 

We’ve been playing since noon. 

They walked through the field. 

In both of the examples above, the prepositional phrases begin with a simple preposition: since is the simple preposition in the first example, and through is the simple preposition in the second example. In both examples, the simple prepositions are followed by an object (noon in the first example) or an article plus an object (the field in the second example). 

These examples also explain how this is a form of preposition. While both of these are simple prepositions, the words we used totally changed the meaning of the sentence. In the first sentence, using since helps us understand the amount of time the person has been playing. That’s because since is a preposition of time! But the simple preposition structure also works in the second sentence, even though we’re using a preposition of movement (through) instead. 

So just like math, prepositional forms let you swap words in and out to create meaning. 

And that’s the definition of a simple preposition! Simple prepositions are used very frequently in the English language, so you’ll probably start to see them everywhere now that you know what you’re looking for. 

#2: Complex (or Compound, or Double) Prepositions

There’s a little disagreement out there about what to call this form of preposition: sometimes they’re called complex prepositions, compound prepositions, or double prepositions. Just know that all of these terms refer to the same thing. 

Complex prepositions are a group of prepositions that function like a simple preposition. That means complex prepositions always consist of more than one preposition (unlike simple prepositions, which only have one). Here are two examples of complex prepositions in a sentence: 

Get these chips away from me. 

She laughed at his joke in spite of herself.

As you can tell from these examples, complex prepositions can appear in two-word units or three-word units. When a complex preposition appears in a two-word unit, it involves two prepositions in a row which are followed by an object. In the first example, away from is our complex preposition, and the object that follows it is me. 

When a complex preposition appears in a three-word unit, it follows a different formula. In three-word units, the first preposition and second preposition are separated by a noun, then the object comes afterward. In the second example, in and of are prepositions, spite is the noun, and herself is the object! 

Remember how we talked about forms of prepositions working like a mathematical formula? That’s definitely the case for complex prepositions! Though there are many complex prepositions (which you’ll see in our list below), the most commonly used formulas for a complex preposition in English are the following: 

To help you pick out complex prepositions when they’re used in sentences, here’s a list of commonly used complex prepositions: 

4 Types of Prepositions and Prepositional Phrases That Convey Meaning 

These types of prepositions are used to convey meaning in a sentence. You can pop them into one of the forms we discussed above to help people better understand specific relationships between a subject and an object in a sentence. Specifically, these types of prepositions describe four different types of relationships: time, space, direction/movement, and agent/instrument. 

These prepositions can be mixed and matched with the preposition forms we just talked about, so most prepositions fit into two categories: one for their form, and another for their meaning. Put another way, a preposition in a sentence can be both a simple/complex preposition and a preposition of time, space, direction/movement, or agent/instrument!

Now, let’s learn a little more about the four types of prepositions that help writers convey meaning.  

#1: Prepositions of Time

Prepositions of time demonstrate relationships between things in terms of when something occurred. Prepositions of time can show the specific, exact time when something happened or will happen. It can also express a more general, extended period of time. 

Take a look at the table below for a list of prepositions that are frequently used to demonstrate relationships in terms of time: 

So how do prepositions express time, exactly? Let’s look at two examples: 

Example #1: Sean will drop off the recycling after work. 

In this first example, after is the preposition of time, and after work is the prepositional phrase. But how is after establishing a time-based relationship here? After establishes time by showing that Sean will perform a specific action—dropping off the recycling—only after he has finished with work. In this case, we can see how these two elements of the sentence relate to one another: one has to end before the other can happen. 

It’s also worth noting that after is also part of a simple preposition...so it’s both a simple preposition and a preposition of time! 

Now that you have a better understanding of how this works, here’s a second example of a preposition of time in a sentence: 

Example #2: I’m going live at ten o’clock. 

In this example, at is the preposition, and at ten o’clock is the prepositional phrase. More importantly, at is establishing a precise time. In this case, the person speaking is going to go live on television at an exact time. Thus, the preposition at establishes that the time-based relationship between the subject and the verb and the object is a precise one. 

You use prepositions of time every day, even if you don’t realize it. Whether you’re giving directions, planning your day, or just telling a story, prepositions of time help us create chronological order. 

#2: Prepositions of Space 

Prepositions of space are used to show where a person, living creature, or other object or entity is located in space (as in, like, physical space in the everyday world, not outer space). 

The words in the following list are classified as this type of preposition, meaning they show where things are located in space, including location in relation to other things, direction, and movement. 

Now that we have a full list of prepositions of space, let’s look at an example of a preposition of space: one example that simply shows where something is located in space. Here we go:

There’s an owl in the chimney!

This example is pretty straightforward. Where is the owl? It’s located in the chimney. There’s a spatial relationship established between the owl and the chimney through the use of the preposition in. 

Prepositions of direction and movement help readers understand movement. In this case, the dancer is lifting his partner off the ground! 

#3: Prepositions of Direction/Movement

Prepositions of space are sometimes broken down into even smaller categories, and two of the categories you need to know about are prepositions of direction and movement. These types of prepositions show movement from one place to another. Because of this, prepositions of direction and movement are often used with verbs of motion. 

Here’s a list of words that are classified as prepositions of direction and movement: 

Prepositions of direction and movement connote that something is moving through space in relation to another object. Check out this example: 

Sophia threw the dart at the bullseye. 

In this example, the dart’s location in space is described in relation to the bullseye’s location in space through the use of the preposition at. We know that the dart is directed toward the bullseye, and since the dart has to move through space in order to actually hit the bullseye, we consider prepositions of direction/movement as falling into the bigger category of prepositions of space!

Here are a few more examples of prepositions that connote direction/movement:

They walked among the wildflowers. 

The festival-goers twirled around the maypole. 

Like the earlier example, both of these examples show that living beings are moving through space in relation to other objects. In the first example, they are moving through space in relation to some wildflowers. In the second example, the festival-goers are moving through space in relation to the maypole. 

One way to recognize prepositions of space that connote direction/movement is to look for a verb right before the preposition, because prepositions of direction/movement often follow a verb in a sentence!

#4: Prepositions of Agent/Instrument

There are also prepositions that can be used to connote a different kind of relationship besides relationships of time or space. These prepositions are known as prepositions of agent/instrument, and they demonstrate a relationship in which one noun performs an action on or toward another noun in a sentence. 

Here are the common prepositions of agent/instrument that you need to know: 

Let’s have a look at an example of a preposition of agent/instrument in a sentence: 

I think the movie was produced by Disney. 

This example conveys a relationship of agency, or power, between a noun and a verb: the movie under discussion in this sentence was produced by Disney. This conveys a relationship in which a group of persons has caused something to occur. In this sentence, prepositions help us understand that Disney has control over the production of the movie. It’s also important to note that prepositions of agency are usually used in sentences that are constructed in the passive voice, like in the example above. 

Now, here’s an example that shows a preposition of instrument. A preposition of instrument is used to describe machines, technologies, and devices. Basically, when you need to explain how a mechanical noun acts toward another noun, you use this type of preposition! Here’s an example: 

She lit the candle with a match. 

This sentence example uses the preposition meaning with to show a relationship between one noun--a match, which is an instrument--and another noun--the candle, which is also an instrument. In other words, the preposition with connotes a relationship in which the match acts upon the candle. Prepositions of instrument almost always describe use of devices, technologies, or other objects. 

3 Top Tips for Identifying Prepositions in a Sentence

As you’ve probably guessed by now, prepositions can be a little bit sneaky in sentences. Sometimes words that are commonly used as prepositions are also used for other purposes, which can make identifying prepositions in a sentence a little bit confusing! We’ve come up with three top tips on preposition grammar to help you spot prepositions in a sentence correctly. 

#1: Break Down the Word Itself 

If you have trouble remembering where a preposition should appear in relation to the object that it modifies in a sentence, you can break down the actual word “preposition” as a memory hack. A preposition appears in front of its object, so you can think of it as being pre-positioned in front of the object. 

Read the examples above one more time. In each one, the preposition comes before the object. And there’s an added bonus: when you can find the preposition in a sentence, you can also find its object, too! 

#2: Remember That Prepositions Are “Anywhere a Cat Can Go”

We’ve already used cats in a couple of our example preposition sentences, but did you know that many people are taught in school that prepositions are anywhere a cat can go? Just think about it: how many videos have you watched of cats fitting themselves into bizarre places? They can go on, in, through, around, under, across, behind, between, through...pretty much any object (especially boxes). And as it turns out—all of those words are prepositions! 

So If you’re looking for a way to remember prepositions of space, location, direction, and movement, just picture a cat playing with a box. If the word you’re using is somewhere the cat can go, then you’re probably dealing with a preposition. 

#3: Watch Out for Verbs...and Look for the Prepositional Phrase  

Something super important to know about words that are classified as prepositions is that they don’t necessarily function as prepositions every time they appear in a sentence. 

This means that you can’t really just glance at a sentence and pick out a single word that is often used as a preposition and be sure that it’s working like a preposition in that particular sentence. You’ve got to look at the bigger picture of the sentence itself to determine whether the word is being used as a preposition! 

So what do you look for to determine whether a word is being used as a preposition? Look at the words around the preposition to see if there’s a prepositional phrase. Remember: a word that is often used as a preposition must show a relationship between the noun and another part of the sentence in order to function as a preposition. 

Additionally, preposition grammar rules indicate that when a word that looks like a preposition comes before a verb phrase instead of a noun phrase, that little word that looks like a preposition isn’t functioning as a preposition at all—it’s functioning as a particle instead. So, in addition to looking out for prepositional phrases, you can also look out for verbs. Here’s an example of what a particle looks like in a sentence: 

We’re going to walk at the market. 

In this example, the phrase to walk might look like a prepositional phrase at first glance, but walk is a verb, not a noun, noun phrase, or pronoun. So, in this case, to isn’t the beginning of a prepositional phrase and isn’t being used as a preposition. However, the phrase at the market at the end of the sentence is a prepositional phrase, since the market is a noun!

What’s Next? 

Prepositions help make your writing clearer, which is incredibly important if you want to ace the writing portions of your standardized tests. Luckily for you, we have expert guides to help you ace your SAT and ACT essays! Click here to learn how to get a perfect 12 on your ACT essay. If you’re aiming to get a perfect 8 | 8 | 8 on the SAT essay, you’ll want to check out this article instead.

You’ll also have to write stellar admissions essays if you want to get into your dream school. Start by getting expert advice on how to tackle the Common App essay prompts, then check out our blog for school-specific tips. We have thorough guides about how to write essays for the top schools in the nation, including Harvard, Yale, Notre Dame, Michigan State, USC, and more!

If you’re interested in grammar because you love to write, you might consider majoring in creative writing. If this sounds like you, you should definitely check out this list of the best 12 creative writing programs in the United States.