Primary 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, etc. These are the words that carry the primary meaning of the sentence. There are also words that 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. 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

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.[1] 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) although for reasons we will come to later, it's more accurately called the genitive.

the teacher's credential
the house's roof
the car's engine

Nouns can also be formed from preexisting verbs, adjectives, other nouns by adding certain 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. (See the section on morphology for more information on this process.)

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 words.

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.

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Notes

[1] Although the claim is not entirely uncontroversial, most linguists believe that every human language distinguishes at a minimum between nouns and verbs.

Pronouns

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 Albertj with hisj 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) *Genevievej made herj 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 female 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.

(14) The graduating seniorsj threw themselvesj a party.

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

(15) *Himself went to the party.

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

(16a) Ron Howard cast himself in his own movie
(16b) *Himself was cast by Ron Howard in his own movie.

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.

Topic: 

Verbs

In terms of their distribution, 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 they are words like can, could, will, would, shall, should, may, might, or must. In most grammar books, auxiliaries are considered a special type of verb, and that is how we will treat them. But 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.

(12) *She can might.[1]

That fact has led some linguists to treat auxiliaries as a separate word category. We will explore the logic for keeping them as a subclass of verbs when we examine the structure of verb phrases.

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 (past tense), and He/she/it walks from I/you/we/they walk. Verbs also take the suffix –ing.

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. Almost every verb does allow -ing to be added, but there are one or two odd cases, such as beware.

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Notes

[1] In some regional varieties, of English, for example in North Carolina, two auxiliary verbs actually can appear together in the so-called double-modal construction, e.g., "I might could loan you the money." Such sentences, though, are ungrammatical for all the standard varieties of English.

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Adjectives

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

(13) She is very slow
(14) *Very fools waste time.
(15) *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

(16) ?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:

(16b) They were present at the assembly.

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Adverbs

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 caategory. 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.

(20) She exercises very frequently.

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Prepositions

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.

(21) in [the yard]
(22) 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. 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:

(23) She walked right into the wall.

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

(24) *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:

(25a) His blind date stood by the fountain.
(26a) The report was completed by a committee of experts.

In (25a), by has an identifiable spatial meaning. This use is not grammaticalized. In (26), 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:

(25b) His blind date stood right by the fountain.
(26b) *The report was completed right by a committee of experts.