What Makes Something a Particle Instead of a Preposition?

Learning about particles can make seemingly confusing things about prepositions finally make sense.

Neal Whitman, Writing for
4-minute read
The Quick And Dirty
  • When a "preposition" is stressed, it might actually be a particle.
  • Preposition and particle use can change over time. For example, "over" is a particle in the phrase "ran me over" and a preposition in the phrase "ran over me."

In our last episode, we talked about the difference between prepositions and particles in order to discuss the famous grammar punch line, “This is the kind of pedantic nonsense up with which I will not put!” Today we’re going to get into two other interesting properties of particles. 

Particles need to be stressed

One phenomenon will be of interest to people who are learning English as a non-native language. Listen to these two sentences. In the first one, “on” is a particle, and in the second, “on” is a preposition:

  • Aardvark slept on.
  • Aardvark slept on the couch.

Did you notice that in “Aardvark slept on,” the particle “on” was stressed? And in the sentence “Aardvark slept on the couch,” the preposition “on” wasn’t stressed. Now if we wanted to, we could stress the preposition, if we were saying something like, “Aardvark slept on the couch, not under it.” But usually, we don’t. On the other hand, if we don’t stress the “on” in “Aardvark slept on,” the sentence crashes. Here’s what it sounds like:

  • Aardvark slept on. 

When I read that sentence to myself, I find myself asking, “Slept on what? Finish the sentence!” Or I imagine that these words are part of a longer sentence that I didn’t catch because the speaker was on mute at first. The whole sentence might be, “This is the couch that Aardvark slept on.” That sentence is OK, even though “on” isn’t stressed, because it’s a preposition. 

If you’re learning English, and haven’t learned the distinction between prepositions and particles, it might seem totally random that “Aardvark slept on” causes English-speaking listeners to scratch their heads, while “Aardvark slept on the couch” is fine.

It can be even more frustrating if you’ve learned that in English, prepositions aren’t stressed, and have spent time and energy practicing not stressing them, only to have people misunderstand you when you say, “Come in! Sit down!” instead of “Come in! Sit down!”

'They ran me over'

The other phenomenon shows how the grammar of a language can change without you even noticing it. In our last episode, we talked about how there are some cases where it’s especially tricky to identify a word as a particle or a preposition. Think about this sentence: 

  • Tom Petty is running down the street. 

Is “down the street” a prepositional phrase, or is “down” a particle and “the street” a direct object of “run”? The answer is: It’s a prepositional phrase. We can tell, because we can replace “the street” with a pronoun, and the sentence is still grammatical: “Tom Petty is running down it.” The pronoun “it” is the object of “down,” and the two words together form a prepositional phrase. 

Now consider this sentence: 

  • Tom Petty is running down a dream.

Is “down a dream” a prepositional phrase, or is “down” a particle and “a dream” a direct object of “run”? This time, “down” is a particle. We know it because if we try to replace “a dream” with a pronoun, we have to put it before the word “down” instead of after, like this: “Tom Petty is running it down.” If we try to keep it after the “down,” the sentence fails: “Tom Petty is running down it.” The only way for that to be grammatical would be for it to mean that Tom Petty is actually running on top of a dream, as if it were a road.

That example was pretty straightforward. Now let’s think about the phrasal verb “run over,” as in “The driver ran over the unfortunate creature.” If we replaced “the unfortunate creature” with the pronoun “it,” how would we say the sentence? Would it be “The driver ran over it,” or “The driver ran it over”? A hundred years ago, the answer would definitely have been “The driver ran over it,” but these days, it’s more likely to be “The driver ran it over.”

I searched the Corpus of Historical American English for examples of the verb “run” followed by “over” and then a pronoun, as in “ran over me.” They peak in the decade between 1890 and 1900, with 40 examples in the corpus. Next, I searched for examples of the verb “run” followed by a pronoun and then “over,” as in “ran me over.” In 1890 and 1900, those examples were in the single digits. They peaked 100 years later, in the 1990s, with 44 examples. They remained in the 30s for the first two decades of the 21st century. In other words, in the 19th century and most of the 20th century, the “over” in the phrasal verb “run over” was a preposition. But these days, it’s used as a particle about twice as often as it’s used as a preposition. 

If you’re writing a book set a hundred years ago, this is one tiny tweak you can make to your language to make your dialogue sound more authentic. An era-appropriate character would be more likely to say, "That car almost ran over me," than "That car almost ran me over."

To sum up, prepositions don’t have to be stressed, but particles do. This is true even when a preposition gets stranded at the end of a sentence, as in “What did Aardvark sleep on?” The verb “sleep” gets stressed, but the preposition “on” doesn’t. But in the sentence, “Fenster partied on,” the particle “on” does get stressed. I’ll leave you with this rule in the form of a riddle:

Why didn’t the preposition get stressed when it got stranded at the end of a sentence?

It wasn’t particular!

About the Author

Neal Whitman, Writing for Grammar Girl

Neal Whitman PhD is an independent writer and consultant specializing in language and grammar and a member of the Reynoldsburg, Ohio, school board. You can find him at literalminded.wordpress.com.