Today’s episode is about parts of speech and the interesting gray area between prepositions and adverbs. Let’s start with the help section of the Grammar Girl Grammar Pop game, which has this rule about labeling parts of speech:

“Sometimes, words you might think of as prepositions act like adverbs. When a word such as over or up is modifying a verb, it’s acting like an adverb, but in Grammar Pop we still call it a preposition. Grammar Pop calls the words in the following sentences prepositions:

1. She needed to speak up.
2. The statue tipped over.

“It’s the difference between what something is and what something does: It’s a preposition doing a job that is typically associated with adverbs. Rational people can disagree about this. It’s a gray area of grammar.”

As a reminder, you may have learned that prepositions are little words like up, over, or with that express time, direction, and spatial relationships, while adverbs modify verbs, adjectives, other adverbs, and entire sentences. (The prepositions up and over in these examples are also a type of preposition called “particles,” but that’s a topic for a future episode!)

This decision to go with what the word is, instead of by what it does, is interesting because it is unusual. In other words, with most gray-area parts of speech, we grammarians do go by the job that the word does in the sentence to make the call. For example, the “-ing” form of a verb can be a present participle, like “The baby is crawling,” but the same -ing word can be a “gerund” instead of a participle. The gerund is the noun form of the -ing verb, like “Crawling is what babies do before they learn to walk.” In that sentence, crawling is the subject, and so it’s acting like a noun, not a verb, even though it technically describes an “action.” And, the -ing words can be adjectives, too! Like this: “Crawling babies can be a real handful.” In that sentence, crawling modifies the noun babies. Even though it seems tricky, we cannot call this third crawling anything but an adjective, because it describes a property of the babies, and is not a verb, nor a noun. You can read more about these -ing forms by clicking this.

The point is, few grammarians would lump all three -ing word types together as one part of speech, and yet, many grammarians keep the “adverb-like” prepositions that we talked about earlier as prepositions, even though they are doing more of an adverbial job. It seems that “adverb” is a part-of-speech category whose members run on a spectrum from “fully adverbial” to “barely adverbial.” In fact, some linguists refer to adverbs that end in -ly, like fortunately or quickly, as “indisputable adverbs”! (2) So why is that? We’ll talk about four possible explanations.

What Makes Some Adverbs Controversial, and Why Do Grammarians Classify “Adverb-like” Prepositions as Prepositions?

Let’s back up and look more closely at those controversial prepositions described in the Grammar Pop instructions. According to traditional grammar, we all agree that the word inside in this sentence is a preposition:

1. Get inside the castle!

We call inside a preposition because it has an object—the castle. But, in this next sentence, many people call the word inside an adverb:

1. Get inside!

They call that inside an adverb because without the castle, there is no object of the preposition, and all that inside can modify is the verb get.

It may seem like a no-brainer to label all prepositions as adverbs when they modify verbs (again, that’s in those cases when they have no object). Indeed, decisions like this are a common problem to solve in related fields like computational linguistics. Computational linguistics is a science that does things like create software to do language-related tasks, such as translate written language, program voice recognition software for when you call an automated 800 number, or tag (which means “label”) the parts of speech of written words. For example, in an early computational linguistics article, the tagging software that the authors describe had an extra portion of code to teach the computer when to call as a preposition, and when to call as an adverb. For example, in this next sentence, the first time we use the word as, it’s an adverb, and the second time, it’s a preposition:

1. The Catskill mountains are not as (adverb) tall as (preposition) the Himalayan mountains.

The first as is an adverb because it modifies the adjective tall, but the second as is a preposition because it acts as a comparison, and the noun phrase the Himalayan mountains is arguably the object of the preposition.

The Adverb/Preposition Distinction Is Not Straightforward

Now, let’s go over some fascinating theoretical arguments for why “adverb” may not always be the best label for those prepositions with no object. Even syntacticians disagree, but their reasons are interesting.

Adverbs tend to be considered grammatically optional.

First, adverbs tend to be considered grammatically optional. In other words, they add detail and meaning to the sentence, but don’t cause the sentence to be wrong if they’re removed. “Jennifer runs fast” and “Jennifer runs,” without the adverb fast, are both grammatically correct. Prepositions, on the other hand, play a much more important role in the grammar of their sentences. In that way, we could argue that in “Get inside!”, inside is not grammatically optional (because “Get!” alone means something else, if anything). This makes inside a lot more like a preposition than an adverb, even though some grammarians would call it an adverb.

A second argument in favor of the preposition label is the fact that the sentence “Get inside!” may be a case of what linguists call “ellipsis.” (It’s not the same as the punctuation, but it’s a similar concept: Think of the way the three-dot punctuation mark is used to show a trail-off of missing words.) Speakers frequently “elide” words, which means that they are not spoken, but they are implied. We know they are there, but it may be redundant to say them out loud. In other words, if I point to the castle and shout “Get inside!” some linguists might argue that inside does indeed have an object—the castle—it’s just that this object is provided by context, and is not needed in the grammar of the sentence. The linguistic study of when context interacts with syntax is called “pragmatics.”

A third pro-preposition point is that these controversial adverbs fail certain syntactic adverb tests. For example, take the prepositions inside, up, around, and over. We know that adverbs can modify adjectives, like incredibly in “She is incredibly smart” (incredibly is an adverb modifying the adjective smart) and they can modify other adverbs, like incredibly in “She drove incredibly fast.” (Incredibly is an adverb modifying the other adverb fast.) However, the preposition around is different: We can’t say “She is around smart,” and if we say “She drove around fast,” around is not modifying the adverb fast. The preposition inside has similar problems: “She is inside smart” and “She is inside fast,” show that inside fails the adverb tests, making many of us inclined to call it a preposition no matter what job it does. (2) This shows that while incredibly is an “indisputable” adverb, prepositions like inside and around when they have no object fall further away on the spectrum of adverbs, so saying that inside is an adverb just because it has no object may not be 100% right. Even though not all adverbs pass all syntactic adverb tests, some members are more controversial than others. Remember that those “indisputable” “-ly” adverb members, like incredibly, on the other hand, are not controversial! We’re all in agreement about those.

Transitivity Is Not Just for Verbs

Finally, here’s the most interesting line of reasoning in defense of the preposition label for words like up in the sentence “She needs to speak up” and inside in “Get inside.” You may have heard of “transitivity” as a property of verbs. For example, snore is intransitive, because it never takes a direct object (a direct object is a recipient of the action), while devour is transitive, because it sounds very strange without a direct object. She devoured. It just sounds weird. In other words, in English sentences, something edible must be devoured. Further, there is an interesting middle ground for verbs that alternate, such as fly: They can be both transitive and intransitive, in different sentences. You can fly a plane, which is a transitive use of fly with the direct object a plane, but you can also just fly. (Wouldn’t that be nice!) Snore, on the other hand, is called “obligatorily intransitive,” because it really can’t alternate or be used transitively (again, “used transitively” means “used with a direct object”). You can’t really snore anything. Another example of an obligatorily intransitive verb is sneeze. Let’s re-cap: “Neil flies (transitive verb) planes (direct object).” “Neil flies (intransitive verb).” You can also read more about transitivity by clicking this.

Now, by the way: Some of you may be trying to find examples of forcing an obligatorily intransitive verb like snore to take an object. A common example people come up with is “But, I can say, ‘He snored the night away’!” That sentence is metaphorical, and it may seem like the night is the direct object of snored, but it technically isn’t. The night is not actually being snored, or affected by the snoring action in any way. This is one of the fun things about unconscious language and grammar rules: We “break” the rules in certain situations, such as when we want to create humor, metaphors and idioms, or poetry. In other words, remember that just because a verb has words after it, that doesn’t mean it is transitive. Here is another example: “Poppy sneezed all day.” In that sentence, sneeze is intransitive, because “all day” is an adverbial expression that indicates the duration of her sneezing action, but not “what” she sneezed, so it is not a direct object.

OK so, when elements such as objects are required after a verb, those are called “arguments” by syntacticians. Arguments can be subjects, direct objects, or indirect objects, for example. Unlike optional words like adverbs, arguments are required by the grammar rules. Verbs take inventory, so to speak. For example, to give (like this):

1. Eleanor gave a house to Kate.

usually requires three arguments: First, a subject: Eleanor to do the giving action. All English verbs require subjects. Second, a direct object: a house. Third, an indirect object: (to) Kate. We know all three are required in this context because “Eleanor gave Kate” sounds very strange. Kate is the indirect object, because she is the recipient of the direct object a house. Indirect objects usually have to or for in front of them, like “I baked a cake for our guest.” You can read more about direct and indirect objects by clicking this.

Prepositions have argument structure, too!

This system of arguments that verbs take, reject, and require is called “argument structure,” and here’s where things get interesting for prepositions: Prepositions have argument structure, too! For example, the preposition by is a transitive preposition. “The dress is by the chair” is fine, but “The dress is by” makes no sense at all. (You may be thinking that the chair in that sentence is the object of the preposition by, and that’s right.)

The point is that viewing prepositions as having transitivity is one way grammarians can reject that adverb label for the adverb-like prepositions. Some linguists theorize that those prepositions with no object are intransitive, the way the verb snore is intransitive, or the way the verb eat can be either one. This line of reasoning points out that when verbs like fly don’t have an object, we don’t re-name the part of speech of the verb; we just say that the verb fly is intransitive in that particular sentence. Therefore, logic suggests not re-naming prepositions as adverbs just because they have no object. In that way, in our “Get inside!” example, you could say that inside is just an intransitive preposition. (2)

What’s neat about this theory is that there are actually a few prepositions that must always take objects, like to and toward. In other words, you can’t say “Andrea ran toward,” with no object. So, those prepositions are obligatorily transitive, like the verb devour. Also parallel to verb transitivity is the fact that most prepositions can alternate, which means both be prepositions (i.e., take an object) and be adverb-like prepositions that do the job of an adverbs. Two examples are prepositions down or around. These are parallel to those verbs that can be both transitive and intransitive, like fly or eat. Finally, there are prepositions that cannot ever take an object, like away and overhead, and so they are obligatorily intransitive prepositions, like our example intransitive verbs snore and sneeze. (2, 4) You’ve probably never heard the term intransitive preposition, but classifying prepositions without objects as intransitive—instead of as adverbs—can even be found in The Cambridge Grammar of the English Language. (3, 5) Welcome to advanced linguistics!

As you can see, the distinction between adverbs and prepositions is an interesting gray area of grammar, and calling the adverb-like prepositions “adverbs” isn’t always the right choice. Just because a preposition does the job of an adverb, it doesn’t necessarily follow that it is no longer a preposition. It seems best to choose the category you prefer as needed—but be prepared with a good defense for your choice!

References

• (1)Brill, E. (1994). Some Advances in Transformation-Based Part of Speech Tagging. Spoken Language Systems Group Laboratory for Computer Science at Massachusetts Institute of Technology.
• (2)Burton-Roberts, N. (1991). Prepositions, adverbs, and adverbials. In I. Tieken-Boon van Ostade, & J. Frankis (Eds), Language: Usage and description (pp. 159–172). Amsterdam: Rodopi.
• (3)Cappelle, B. (2005). The particularity of particles, or why they are not just ‘intransitive prepositions’. Belgian Journal of Linguistics, 18, 29–57.
• (4)Emonds, J. (1972). Evidence that indirect object movement is a structure-preserving rule. Foundations of Language, 8(4), 546–561.
• (5)Huddleston, R., & Pullum, G.K. (2002). The Cambridge Grammar of the English Language. Cambridge: Cambridge University Press.
• (6)Myler, N. (2017). Personal communication.