Adapted by Matt Garley from Hagen, Karl. Navigating English Grammar. 2020. Licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.

One of the first things that people noticed when they started thinking about language as language was that words tend to fall into categories and that the members of these categories behave in similar ways. The traditional name for those categories is the “parts of speech.” In this chapter, we will look at these word categories and see how the traditional account is somewhat misleading, as well as inaccurate. With a more accurate idea of word categories, we will be equipped with the basics that we need to begin studying sentence structure.

The Traditional View of Parts of Speech

You may have forgotten much of the grammar you were taught in school, if you were taught any at all, but most people can remember the parts of speech, at least the major ones. What is a noun? You probably said “a noun is a person, place, or thing.” A verb? It describes an action, right? What about a preposition? You may have had more difficulty here, but perhaps you learned that prepositions tell you what an airplane can do to a cloud (go through, under, into, etc.). All of these definitions are well-entrenched in our educational system, but linguists are happy with none of them. If we scrutinize them, the traditional parts of speech turn out to be problematic. Consider the traditional definitions of noun and verb:

Noun: A noun is a person, place or thing.

Verb: A verb describes an action or state of being.

These definitions cover what we might call prototypical cases. Nouns often do label objects in the real world (car, tree, apple, etc.) and verbs most commonly express action (run, play, eat, etc.). But what do we do with abstract nouns like love or destruction? One easy way out is to add “idea” to the definition, but this change comes at a severe cost, for “idea” can be taken to encompass just about everything. Consider sentences such as

(1) John gave him a shove.

(2) John shoved him.

What allows us to say that shove in sentence (1) functions as a noun, but shoved in sentence (2) functions as a verb? The meaning of both sentences, after all, is essentially the same. And how do we account for verbs like hear or undergo? In a sentence like

(3) Vivica underwent a tonsillectomy as a child.

the subject does not really perform an action, nor does the verb describe a mere state of being. It actually describes a change of state. If we broaden our definition to say that a verb tells us something about some person or thing, it becomes difficult to explain the difference between verbs and adjectives. The traditional definitions of parts of speech often fail because they look for semantic definitions. These definitions may cover the usual situations acceptably, but any definition that covers all cases becomes so vague as to be useless for making discriminations. Another problem with the common way of presenting parts of speech stems from their origins in Latin grammar. The term part of speech, and most of the labels themselves, were borrowed from the study of Latin.^[1] When English was first subjected to grammatical analysis, Latin was the language of educated Europeans, and it was presumed to represent an ideal, logical grammar. Therefore the earliest writers of English grammar books simply applied the terminology and classification they knew from Latin to the description of English. Because the two languages have significant grammatical differences, however, the fit was not perfect. Most Latin grammars described eight parts of speech: nouns, pronouns, verbs, adjectives, adverbs, prepositions, conjunctions, and interjections. If one didn’t look too closely at the details, these categories worked, more or less, for English. But there were many problematic cases that troubled grammarians from the start. How, for example, should one handle the word the, or the word to when it appears in front of a verb? Latin had no direct equivalent to either word, but some grammarians tried to force these words to fit the Latin categories anyway. Therefore, the was considered an adjective and to (even in to go) was called a preposition. Other grammarians disagreed, creating new categories for these words. This disagreement was never resolved in traditional grammar, and to this day, different textbooks make conflicting statements about these words.^[2]

The Linguistic View

Given all this confusion over the concept of parts of speech, it’s reasonable to ask if we can’t just get rid of the concept completely. Why do we really need to know what a noun is? In fact, the problems with traditional parts of speech have prompted some linguists to abandon the term part of speech completely. They have not, however, given up on the idea behind the label. The term part of speech simply means “a word category.” In other words, it reflects the important observation that words can be grouped into categories because they behave similarly. For example, consider how we can complete the following sentence frames:

(4) She has no ____.
(5) She can ____.

The first sentence can be completed with words like bicycle, shoes, worries, ability, home, chill, etc., that is, with nouns, but not with words like went, happy, in, or cheerfully (verb, adjective, preposition, and adverb respectively). The second sentence works with words such as hide, fly, delay, lie, cry, etc. (verbs), but not shoes, beautiful, happily, into, etc. Such sentence frames show that there’s more to a word than its meaning. Words also belong to categories, and knowing membership in a particular category lets us predict where the word can fit in the sentence.

(6) *My sons both graduation high school.

A sentence like (6) is ungrammatical because the slot that graduation occupies in the sentence requires a verb, not because the general meaning of graduation is inaccurate.

Some linguists avoid the term parts of speech and prefer to speak simply of categories. What is gained by changing the terminology?

It is true that “parts of speech” is misleading if we take the expression literally, as components of language. Clearly, there are many more parts to language than word categories. On the other hand, “part of speech”, as a term of art, differs little in its basic meaning from category.

It’s really the implication of the term–its association with old grammar books–that causes some to avoid it. I, however, find it hard to see enough difference between the two terms to justify abandoning so familiar a term as “part of speech.” Although traditional definitions are muddled, in practical terms, older grammarians meant largely the same thing as modern linguists do with major categories such as noun, verb, or adjective. Even where old fashioned grammarians could not explain the parts of speech adequately, they would still assign the majority of words to the same categories linguists do. (The exceptions, we will see shortly.) In other words, even if traditional grammarians did not define what they were doing very well, their intuitions about these categories led them to many of the same conclusions. So the lexical categories are essentially the same thing as the parts of speech. The fact that the details differ doesn’t really affect that essential similarity.

The insistence upon the generic term category, however, does have the virtue of emphasizing just what the parts of speech are, something that is opaque in the traditional term. For that reason, we will use part of speech and category interchangeably, keeping in mind that using the traditional term does not imply we accept the details of traditional classification uncritically. Instead, we will examine how these categories can be redefined to better reflect the way they actually work.

Testing Category Membership

If we are going to do more than simply accept the traditional parts of speech uncritically, we need to establish some sort of theory of word categories, that is, a set of principles that will let us decide where the traditional categories work and where they need revision. Armed with this procedure, we will find that traditional grammars describe some categories that have no real existence in present-day Englishes. They also conflate other categories which are actually distinct.

Our basic procedure will be to look for elements that are grammatically distinct in English. In other words, we must find structural reasons to distinguish one item from another. For example, we can justify distinguishing verbs from nouns based on the relationships they enter into:

(7) Brown should denounce the need to memorize grammatical definitions.
(8) Brown’s denunciation of the need to memorize grammatical definitions (was well-intentioned)

In example (7), denounce belongs to a category (verb) that can take an -ed inflection to indicate past time (for example, “Brown denounced it.”). It can also follow an auxiliary verb (in this instance, should). It can also, in turn, be followed by a noun phrase (the need) that functions as something called the direct object. (Don’t worry if some of these terms are unfamiliar. We will cover them in the upcoming chapters.) One way to speak about these possibilities is to say that denounce can enter into a variety of structural relationships with other elements in a sentence. These relationships are not a matter of the word’s meaning. Notice that a wide variety of different words can replace denounce. If we were to substitute them, the sentence’s meaning would change entirely. Yet all those words appear in the same structural contexts.

The word denunciation in (8) enters into an entirely different series of relationships, even though its meaning is quite similar to that of denounce. It can be preceded by a definite article (the) or a noun phrase marked with the so-called “possessive” (‘s), it can take a plural -s inflection, and it can be modified by an adjective (for example, “Brown’s quick denunciation). If we try to make denunciation fit into any of the patterns that work for denounce, we get ungrammatical nonsense:

(8a) *Brown’s denunciationed of the need to memorize grammatical definitions.
(8b) *Brown’s can denunciation of the need to memorize grammatical definitions.
(8c) *Brown’s denunciation the need to memorize grammatical definitions.

As a result, we say that denunciation belongs to a different category (noun).

We will use both procedures repeatedly both to explain how we arrive at our categories and to figure out which category any particular word belongs to.

Another important point about word categories is that they exist within a hierarchy. That is, we will recognize both primary categories and subcategories. For example, we accept the primary category of noun, but not all nouns behave the same way. Words like Gina and car are both nouns and share properties such as the ability to appear as the principal word in a subject. But they also differ in the words that appear with them. Car, as long as it is singular, must appear with a word like the or a. Gina, on the other hand, cannot appear with these words:

(9) *Car is in the driveway.
(10) *The Gina was late for work.

We therefore say that car and Gina belong to the same primary category, but different subcategories.

Lexical Categories

Contemporary linguistics describes some word categories differently from traditional grammar books, and introduces several new distinctions.

One distinction that is sometimes made is between lexical categories and functional categories.
Lexical categories contain the content words–nouns, verbs, adjectives, and adverbs. These are the words that carry the primary meaning of the sentence. Words that belong to functional categories–determiners, auxiliaries, prepositions, coordinators, and subordinators, for our purposes–carry little specific meaning of their own. Their main purpose is to serve as the glue to hold the content words together. Such words belong to functional categories. Although this distinction is conceptually useful, it’s not always easy to assign categories clearly to one group or the other. Prepositions, as we will see, have some lexical qualities and some functional qualities.

For that reason, we will not make too much of the lexical vs. functional distinction, though it’s interesting to note that the lexical categories are where most of the change in a language’s vocabulary over time happens. Instead, we will simply describe the primary categories. We will examine how these categories work in more detail as we learn more about sentence structure. For now, here’s a brief overview.

Nouns (N)

Although I have already tried to show why the traditional definition of a noun (person, place, or thing) is inadequate, now that we have come to define what nouns are, I am going to start with that definition anyway. Am I contradicting myself? Not really. Nouns do refer to people, places, and things, but that doesn’t exhaust the extent of their reference. People, places, and things are prototypical nouns. If we’re studying a new language, the category that we will call “noun” in that language will be the one that includes these core objects.^[3] We will start with these core nouns, observe the patterns that they exhibit, and then use those patterns as a structural test for other words whose category membership may be less clear.

Let’s begin with a few examples of such core nouns: teacher, house, car.

All of these words use the same suffixes. They change form to distinguish singular from plural by adding -s:

One teacher, two teachers
One house, two houses
One car, two cars

They also take a different suffix that is traditionally called the possessive (‘s for singular nouns, s’ for plural ones). Note that in some cases, an alternative term for this form is the genitive.

the teacher’s lesson plan
the house’s roof
the car’s engine

Nouns can also be formed from preexisting verbs, adjectives, other nouns by adding certain derivational suffixes, e.g., -ment, -tion, -hood, etc. So the presence of such a suffix is good evidence that the word you are looking at is a noun.

These morphological tests work for a wide variety of nouns, but not all. For example, there are some nouns that form the plural irregularly (e.g., mouse/mice), or show no difference in form at all (e.g., sheep, deer, etc.). Nevertheless, we still want to assign these words to the same category because in other respects they behave just like the more regular nouns.

Another set of tests looks at the context in which a word can appear in phrases or sentences. As was indicated above, nouns can appear in sentence structures such as the frame in (4), repeated here for convenience:

(4) She has no _____.

Nouns can also appear as the subjects of sentences:

(11) Deprivation is growing among the unemployed.

Nouns also follow certain function words known as determiners (see below), such as the, a(n), my, that, etc. Thus we can say the enrollment, but not *the enroll.

In this course, we will take pronouns to be a subcategory of noun, for simplicity’s sake. Pronouns are words like he, she, or you that let us cross-reference another entity somewhere else in the discourse or in the real world. Traditional grammars state that pronouns replace nouns, but it would be more accurate to say that they replace noun phrases.

(12a) [The airplane parked on the tarmac] appeared damaged.
(12b) It appeared damaged.

In (12b), the pronoun it does not replace just the word airplane of (12a); it replaces the entire string of words, the airplane parked on the tarmac. Replacing only airplane with a pronoun yields an ungrammatical sentence:

(12c) *The it parked on the tarmac appeared damaged.

Pronouns serve the same functions in a sentence that nouns do, most notably they are the heads of noun phrases. They largely observe the same syntactic rules as nouns, for example subject-verb agreement. For these reasons, we will consider pronouns to be a special type of noun rather than an independent word category.

We will use the term referent for the entity to which the pronoun refers. The referent does not necessarily have to be named linguistically. For example, if you and I are standing on a street corner and observe an automobile weaving in and out of traffic at a high rate of speed, you might say to me, “He’s driving recklessly.” The context of the situation tells me that the referent for he is the car’s driver without your needing to use that noun phrase. However, pronouns often do refer to other noun phrases, and in this common situation those noun phrases are called antecedents.

Sometimes, we will need to note what pronoun refers to what antecedent. In this case, we will use a subscript notation. For example:

(13) Genevieve helped Albert_j with his_j physics homework.

In (13), the letter j indicates that the pronoun his refers to Albert. In other words, j serves as a co-referencing variable. We can use such subscripts to make assertions about particular interpretations of pronouns. For example:

(14) *Genevieve_j made her_j a sandwich.

We mark (14) as ungrammatical not because it has no sensible interpretation but because her cannot be understood to apply to Genevieve. If her referred to any ‘her’ other than Genevieve, the sentence would be acceptable.

Pronouns come in several varieties: Personal pronouns I, you, he, she, etc. usually refer to a previously mentioned noun phrase or to a clearly implied person. Reflexive pronouns myself, yourself, themselves, etc. most commonly refer to the subject of the clause they are in.

(15) The graduating seniors_j threw themselves_j a party.

Because of this requirement that reflexives refer to the subject, reflexive pronouns usually cannot appear in subject position

(16) *Himself went to the party.

For the same reason, transitive verbs with reflexives in the direct object cannot be made passive:^[4]

(17a) Ron Howard cast himself in his own movie
(17b) *Himself was cast by Ron Howard in his own movie.

Additional types of pronouns:

Indefinite pronouns: somebody, anyone, everything, nothing, etc. don’t refer to specific nouns.

Interrogative pronouns: what, who, or whom, replace a noun phrase in forming a question.

Relative pronouns: who, whom, which, whose, replace a noun phrase in a relative clause.

Interrogative and relative pronouns occur as parts of more complex structures, which we will study in a later chapter.

Finally, “possessive pronouns”, which are forms like my, your, our, his, her, etc., when they precede a noun, will be treated as determiners, rather than as nouns.

(18a) Her car was on fire.

(18b) The car that was on fire was hers.

In (18a), ‘her’ is a determiner–it can be substituted with other determiners, like ‘the’. In (18b), the possessive pronoun is in the object position, and is acting as a noun.

Verbs (V)

In terms of their distribution, main verbs, lexical verbs, or simply ‘verbs’, are words that can appear after auxiliaries. In the frame sentence (5), repeated for convenience, can is the auxiliary:

(5) She can ____.

We will have more to say about auxiliaries later. For now, we can simply note that one test for verb status is whether it can fill in the blank in sentence (5).

Morphologically, verbs change form to distinguish tense, and, in the present tense, the third-person-singular from other persons and numbers. Thus we contrast They walk, the present tense, from They walked, the preterite (simple past tense), and He/she/it walks from I/you/we/they walk. Verbs also take the suffix –ing, and can appear in another past-tense form, the participle, which we’ll introduce in another chapter.

Note, however, that these morphological tests don’t work for every verb. Just as there are some exceptions as to how nouns form the plural, there are some exceptions to how verbs form the preterite and some other forms. In terms of meaning, it is important to recall that defining verbs as ‘action words’ is not always reliable. In Jane exists, ‘exists’ is not what we would generally think of as an action. Thus, it’s better to think of verbs as generally expressing the main situation, relationship, or action of a sentence (but other tests are better).

Verbs can be categorized in different ways; one of the main ones we will discuss later is the ways in which they act toward objects and other predicative complements. We will distinguish in another chapter between linking verbs, intransitive verbs, monotransitive verbs, ditransitive verbs, and complex verbs.

Finally, note that verbs often have phrasal relationships with preposition-like words that change the core meaning of the verb. Consider the ‘receive’ meaning of ‘get’ in (19a) and how it changes in (19b-d)–none of these have anything to do with receiving something! In these cases, we’ll call ‘out’, ‘up’, and ‘over’ examples of another category, particles, which go together with verbs to make what are often called phrasal verbs.

(19a) I will get a fishing rod for my birthday.

(19b) I will get out a fishing rod when it’s time.

(19c) I will get up to go fishing tomorrow.

(19d) I will get over the bad fishing trip I had eventually.

Adjectives (Adj)

Adjectives typically specify characteristics of nouns, or they limit the application, as in “the large refund,” “an enthusiastic participant,” or “purple prose.” Most often they appear before a noun, although they can also appear in their own phrases after certain verbs known as linking verbs, as in “Wilma looks cheerful.” or “They were happy.”

Morphologically, most adjectives are gradable. That is, they express the grammatical category known as degree. The basic form of the adjective, which expresses a quality, is known as the positive degree. To express a greater intensity of one of two items, the comparative degree is used, either by adding the suffix –er or with the word more and the basic adjective. To express the greatest intensity among three or more items, the superlative degree is used, either with –est or most.

Gradable adjectives can be tested by adding the word very in front of them. Thus

(20) She is very slow
(21) *Very fools waste time.
(22) *He very adores her.

Some adjectives, however, describe an all-or-nothing state, and aren’t gradable. The very test sounds rather odd with these words, as in

(23a) ?They were very present at the assembly.

In such cases, the very test won’t help us decide whether present is an adjective. Notice, however, that present does pass the other structural tests for an adjective given above. For example, it can appear after a linking verb like were:

(23b) They were present at the assembly.

Adverbs (Adv)

In traditional grammar, adverb was a catch-all category for everything that was difficult to analyze. Unfortunately, this had the effect of making the category heterogeneous. Some words that are traditionally called adverbs show very different distributions from other words in the same category. In some cases, we will not categorize these words as adverbs at all. We will note such cases as they occur in later chapters. We will begin, however, with the most obvious cases.

Adverbs are characteristically used to modify verbs. That is, they perform the same function for verbs that adjectives do for nouns. And indeed, adjectives and adverbs are often closely related, but they do not appear in the same function:

	Modifying Nouns	Modifying Verbs
adj.	new cars	*They new drove.
adv.	*a suddenly change	It changed suddenly.

Many adverbs can also modify adjectives, and some can also modify words of other categories (except nouns), as well as complete phrases and clauses.

verb modifier: The pedestrian appeared suddenly.
adj. modifier: The suddenly hazardous situation took us by surprise.
clause modifier: Suddenly, the pedestrian stepped into the street.

verb modifier: I almost wrecked the car.
adj. modifier: His confusion was almost comical.
adv. modifier: She almost never misses a meeting.
prepositional phrase modifier: The situation was almost beyond repair.

(Note: if you’re having trouble seeing why these adjectives and adverbs are modifying the things that I say they are, you might want to read the chapter on phrase structure, and then return to this section.)

Morphologically, many adverbs are formed from adjectives by adding the suffix –ly. Like adjectives, they are also frequently gradable, and can use the comparative and superlative. The very test also works for adverbs.

(24) She exercises very frequently.

Secondary Categories

The remaining categories are called secondary not because they are unimportant but because they have many fewer members than the primary categories. There are tens of thousands of words in the primary categories but only a handful of words in the remaining categories. The membership of these categories does change, but much more slowly over time.

Prepositions (P)

A preposition relates one unit in the sentence to something else in the sentence. Prepositions often express relations of space or time, or they mark various grammatical roles. Words like in, to, over, and through are prepositions. As their name implies, they precede something, usually a noun phrase. The phrase that follows a preposition is called the object of a preposition.

(25) in [the yard]
(26) throughout [the ages]

Prepositions are slightly different from the categories we have already examined. They often have distinct meanings of their own, but many prepositions play a more purely functional role. Prepositions form a small, relatively closed set of words. There are only a few hundred prepositions in English, as opposed to tens of thousands of nouns, verbs, adjectives, or adverbs. It’s easy to invent new nouns, verbs, adjectives, or adverbs. New prepositions, however, are added to the language only rarely.

Prepositions do not have inflectional endings, so we cannot apply morphological tests to prepositions. However, like adjectives, many prepositions are gradable. These prepositions can be preceded by degree words such as right or straight:

(27) She walked right into the wall.

Not every preposition is gradable, however. Of is a preposition, but it cannot be modified by right/straight.

(28) *The relaxed days right of summer were my favorite.

The ungradable prepositions have what are called grammaticalized uses. In other words, the preposition’s meaning is not distinguishable from the grammatical construction in which it occurs. For example, compare the use of by in the following sentences:

(29a) His blind date stood by the fountain.
(30a) The report was completed by a committee of experts.

In (29a), by has an identifiable spatial meaning. This use is not grammaticalized. In (30a), however, by has no spatial meaning. Indeed, it’s hard to say what independent meaning it has. Its function is grammatical: it specifies the following noun phrase (a committee of experts) as the actor in the sentence. Notice that (25a) is gradable, but (26a) is not:

(29b) His blind date stood right by the fountain.
(30b) *The report was completed right by a committee of experts.

As noted in the section on verbs, we will consider the particles that appear with phrasal verbs, like ‘get up‘, as the same category and label (P) as prepositions for simplicity, while keeping in mind that they function quite differently (in that they don’t take complements of their own).

Determiners (D)

Determiners are words that appear before nouns and specify ideas such as definiteness and quantity. Traditional grammar books often lump determiners in with adjectives and pronouns, but we will treat them as a primary category. Determiners play an important role in noun phrases. For now we merely list the most common determiners, and some subcategories which may be familiar, including articles, demonstratives, quantifiers, and numerals. We will return to them in more detail when we look at noun phrase structure.

Articles

The definite article, the, is used to introduce something that can be identified uniquely within the context of the utterance or of general knowledge. For that reason, the is typically used for “old” information. If I say “bring the chair,” I assume you already know which chair I’m talking about.

The indefinite article, a/an is used for situations were the reference is not uniquely identifiable. If I say “bring a chair”, I don’t have any particular chair in mind.

Demonstratives

The demonstratives are this, that, these, and those. Like definite articles, they refer to old information. But they also point to specific things: this book or those children.^[5] That “pointing” establishes a relative spatial relationship, which is reflected in the contrast between this/these, used for items that are close to the speaker, and that/those, used for items that are further away from the speaker, relatively speaking. Note that this, that, these, and those can also be used alone as pronouns, when they do not precede or introduce a noun.

Quantifiers

Many determiners express a notion of quantification. That is they specify how much or how many of the head noun there are. Here’s a list of some common quantifiers:

all	any	both	each
either	enough	every	few
fewer	less	little	many
more	most	much	neither
no	none	several	some
sufficient	what	whatever	which
whichever

Numerals

One kind of determiner that deserves separate attention is the numeral.^[6] Numerals appear in one of two forms: cardinal (one, two, three, etc.) and ordinal (first, second, third, etc.). When cardinal numerals appear in front of a noun in order to quantify it (two birds, four cats, etc.) they are best treated as determiners. Ordinal numerals, on the other hand, might best be treated as adjectives that come after other determiners (the first prize, our fifth date, etc.) Numerals can also appear as independent nouns in their own right. We will return to this point when we examine the structure of noun phrases.

Auxiliaries (Aux)

In most grammar books, auxiliaries are considered a special type of verb, but we will treat them as a separate category. It’s important to note that auxiliaries do not behave like most other verbs. In particular, they fail most of the tests for verb-hood given here. For example, the frame sentence (5) cannot be filled in with another auxiliary.

(31) *She can might.^[7]

What’s relevant for now is that, while every sentence has to have a verb, auxiliaries are optional, only appear with (specifically, before) a main verb, and cannot substitute for a main verb. The words be, do, and have can sometimes function as auxiliary verbs, and sometimes function as main verbs. Other than these, there is one special subcategory of auxiliaries we’ll deal with now.

Modals

Modal verbs or modals are words like can, could, will, would, shall, should, may, might, or must.  These are special because they do not have any other inflectional forms, like other verbs (and auxiliaries) do.

Coordinators (Co) and Subordinators (Sub)

Traditional grammars typically have a category called the conjunction and distinguish between coordinating conjunctions and subordinating conjunctions. In point of fact, these two classes of words do not behave the same way at all, and so there is no good reason to think they are subtypes of a larger category. For that reason, we will treat these words as belonging to separate categories.

Coordinators (Co)

Coordinators are words that join grammatically equal units together. The principal coordinators are and, but, or, and nor. A common mnemonic device some have learned is ‘FANBOYS’–for, and, nor, but, or, yet, so. Note that for is often a preposition, and yet and so are often used in other ways; use of these three as coordinators is becoming less common in modern English.

Subordinators (Sub)

Words whose function is to establish an unequal grammatical relationship, (e.g., because, since, whether, if).

(27) She asked me whether it was raining

Most subordinators can also function as other parts of speech: to can be prepositions, that can be a determiner, etc.), and so we will return to look at subordinators, and how to distinguish them from other parts of speech, more closely in later chapters–particularly when we consider subordinate clauses.

Interjections (Int)

Interjections are words like oh, hey, ouch, or aha. They stand apart from other parts of speech in that they do not combine with other words in larger syntactic structures. Their primary function is to express feeling rather than to make a proposition about something. Some words—particularly curses like damn—are primarily verbs but can function as interjections:

(32) Damn, I’m late for work again.