Agentive: A noun phrase has an "agentive" role when it refers to the entity that initiates or performs the action denoted by the predicate. For an entity to be an agent, it must be acting intentionally. For example, in the sentence The truth angered Sally, the noun phrase the truth is non-agentive; although it is causing the "angering," it is an inanimate entity and therefore cannot be acting intentionally. By contrast, in the sentence The teacher angered Sally, the noun phrase the teacher could be agentive if the teacher in question was acting intentionally to anger Sally.

Antecedent:The noun that indicates what a pronoun refers to. For example, in the sentence John said that he would fix the desk, John is the antecedent of he.

Aspect: A feature that indicates how an event or state extends over time. For example, the progressive aspect indicates that an action is or was ongoing, as in I am having lunch (ongoing in the present) or I was having lunch (ongoing in the past). The perfect aspect indicates that an event is completed, as in I’ve had lunch.

Auxiliary: Sometimes known as "helping verbs," auxiliaries like be, do, and have are used alongside main verbs to express tense and aspect, among other things. For example, in the sentence I am talking to Mary, the auxiliary am indicates that the event is taking place in the present, while in I was talking to Mary, the auxiliary was indicates that the event was taking place in the past. There are a number of ways to diagnose whether a verb is an auxiliary or a main verb. For example, auxiliaries undergo subject-auxiliary inversion to form questions (He was talking to Mary. / Was he talking to Mary?) while main verbs cannot (He talked to Mary. / *Talked he to Mary?). Auxiliaries can also have contracted negation, as in didn't or wasn't, while main verbs cannot (*talkedn't or *sawn't).

Beneficiary: The entity that receives or benefits from a predicate (see glossary entry herein). For example, in the sentence I bought flowers for my mom, the indirect object my mom is the beneficiary of the action bought.

Cleft: A sentence beginning with It and a form of be, followed by the phrase that the speaker is drawing attention to (in turn followed by old information). For example, the sentence It was a hotdog that I ate is a cleft that draws attention to the particular item that was eaten, in this case a hotdog; the fact that eating took place is old information.

Complementizer: A word like that, if or for that introduces an embedded (or subordinate) clause. For example, in the sentence I think that Mary is nice, that is a complementizer that introduces the embedded clause Mary is nice. In the sentence I’m hoping for Mary to be there, for introduces the embedded non-finite clause Mary to be there.

Coreferential: Two or more noun phrases are “coreferential” if they refer to the same entity. For example, in the sentence My mom thinks that she is a good singer, the noun phrases my mom and she refer to the same person, so they are coreferential; likewise, in the sentence I bought this shirt yesterday and already stained it, the noun phrases this shirt and it are coreferential.

Count noun: Nouns that describe discrete, countable things (like books, marbles and people). They can be preceded by indefinite articles and numbers (a book, four people) and occur with many (rather than much), as in the sentence How many people were at the party? They can also occur with fewer, as in the sentence There are fewer chairs at the table than we need.

Declarative: A type of clause that makes a statement as opposed to a directive (imperative) or a question (interrogative).

Ditransitive verb: A verb that takes two objects -- a direct object and an indirect object. For example, in the sentence I gave Mary a book, the verb gave takes two objects: Mary and a book.

Existential interpretation: Indicating that a certain individual or group exists or is performing an action. For example, the sentences There are beavers gnawing on the log and Beavers are gnawing on the log indicate that there is a group of beavers performing the action of gnawing on a log. They do not comment on the behavior of beavers in general, as a generic interpretation would.

Existential sentence/construction: A type of sentence that specifies the existence of an entity or entities (often in a particular location or at a particular time). Existential is also used to describe particular parts of existential constructions, such as “existential there” to refer to the there in sentences like There is a book on the table.

Expletive: In linguistics, the term expletive does not refer to a curse word, but rather refers to something that is essentially meaningless, but serves as a kind of syntactic (grammatical) placeholder. The most common expletive words in English are there and it. For example, in the sentence There is a dog outside, there is an expletive. In the sentence It is raining, it is an expletive.

Finite: A finite verb has tense and can function as a main verb. A finite clause has tense, either marked on the main verb or on a modal or auxiliary.

Focus: A way of emphasizing a certain part of the sentence, which usually concerns new or contrastive information. There are many ways of doing so. One is to use stress to make the sound of the word or words more prominent, as in the sentence MARY enjoyed the movie. Another way is to use a cleft, as in It was Mary who enjoyed the movie.

Generic (interpretation): Referring to individuals or things of a certain type in general. For example, the sentence Beavers build dams has a generic interpretation, meaning that, in general, beavers build dams (regardless of whether or not any individual beaver actually builds a dam). In contrast, in a sentence like Beavers are gnawing on the log the interpretation is not that in general beavers gnaw on the log, but rather that some specific beavers are doing so.

Idiolect: The grammar used by a specific individual. Every person’s idiolect is slightly different -- dialects are groups of similar idiolects, and languages are groups of similar dialects.

Ill-formed: Judged unacceptable by a native speaker in terms of grammar or meaning. For example, the sentence Dogs like she is ill-formed for most English speakers. Most English speakers judge this sentence unacceptable because it does not conform with their mental grammar, which requires the object pronoun to be her rather than she. The sentence Green ideas sleep is ill-formed because native speakers judge that it does not have a sensible meaning. Many of the sentences on our website are ill-formed for some speakers but not for others.

Imperative: A clause type used to issue a directive. These include commands (e.g. Go away!), requests (e.g. Pass the salt, please.), invitations (e.g. Help yourself!), and suggestions (e.g. Remember to take your medicine).

Inflection: Changes to a word by virtue of functional properties, like tense, aspect, person/gender/number agreement and case. Adding -ed to the end of a verb to make it past tense is an example of inflection; as is adding -s to a noun to make it plural or changing he to him when it appears in object position. Inflection is contrasted with “derivation” which are processes that change a word’s part-of-speech or meaning.

Interlocutor: A participant in a conversation — either the person speaking, writing or signing (the speaker) or the person hearing, reading or seeing the words being produced (the addressee).

Intransitive verb: A verb that does not take an object. For example, in the sentence I walk slowly, the verb walk is intransitive.

Island: A part of a sentence out of which words and phrases cannot be moved. Words and phrases are often moved around in a sentence. For example, when forming a question from a declarative sentence, the wh-word (who, what, where, when, etc.) moves to the front of the sentence:

1) a. Mary will see an actor.

b. Which actor will Mary see?

2) a. You claimed that Mary saw an actor.

b. Which actor did you claim that Mary saw?

However, words cannot move out of islands. For example, the question in (3b) is unacceptable because it would require the wh-word to move out of an island, indicated by square brackets:

3) a. You believed [the claim that Mary saw an actor].

b. *Which actor did you believe [the claim that Mary saw]?

Main verb: The verb that describes the primary action or state that the sentence is about. In the sentence I have talked to Mary already, the main verb is talked, whereas have is an auxiliary.

Marginal: A sentence is "marginal" for a given speaker if it does not fall clearly into either the category of "well-formed" or "ill-formed" (see glossary entries herein). The speaker might recognize the construction or not feel it is entirely unacceptable when heard from someone else but feel awkward or not-quite-right using it themselves. 

Mass noun: Nouns that are syntactically uncountable (like sand, water, or furniture). They cannot be preceded directly by numbers (*one sand, *four furnitures) or indefinite articles (*a sand); they need a unit in order to be counted (one grain of sand, four pieces of furniture). These nouns occur with much (rather than many), as in the sentence How much sand is in your hair?, and less rather than fewer.

Modal: Words like must, can, would and should that occur alongside main verbs (as in We can swim in the lake) and indicate notions like necessity, possibility, ability and more. Like auxiliaries, modals can typically have contracted negation (can’t, wouldn’t) and undergo subject-auxiliary inversion (Should Mary come to the party?). Some modals, sometimes called periphrastic modals or quasimodals, do not exhibit these properties. Examples include got to, able to, and have to (as in “I have to go to the store today.”): they convey the notion of necessity but do not take n’t, nor do they invert with the subject.

Morphology: The study and description of the form of words and their parts. Also used to refer to the parts of words themselves, or the forms words may take. For example, “plural morphology” refers to the ending -s in the word books, or to the vowel changes in plural feet (from singular foot).

Negative polarity item (NPI): A word or expression that can only occur after a negation or in a related expression such as a question or a conditional sentence. The bolded words in Have you ever eaten a frog? or I haven’t been there in years are NPIs. They cannot occur in the corresponding positive declarative sentences (*You have ever eaten any frogs, *I have been there in years).

Non-finite: A non-finite verb does not have tense and cannot function as a main verb. In English, non-finite verbs include infinitives (to eat), gerunds (eating) and participles (eaten). A clause with a non-finite main verb (In order to go there…) is a non-finite clause and doesn't constitute a complete thought on its own.

Participle: A form of a verb that can combine with helping verbs to create various tenses. English has present, past, and passive participles.
Present participles end in -ing in English. They can combine with a form of to be to create the present progressive tense (as in She is running), or they can serve as adjectives (as in I'm looking for running water).
Past participles combine with auxiliary have to form the perfect tense, as in She has written four pages today. In English, they usually end in -en (eaten, taken), -ed (worked, baked), or -n (thrown, drawn).
Passive participles combine with a form of be to form the passive voice, as in The pictures were taken on Monday. In English, the past participle and passive participle of a verb look identical, but we label them differently because they have different functions.

Passive participle: The form of a verb that combines with a form of to be to create the passive voice, as in Nothing was taken from my office, where taken is a passive participle. See entries on "Participle" and "Passive voice" for further explanation.

Passive voice: A way of constructing a sentence without mentioning the entity that performs the action of the verb. For example, the sentence The floors are cleaned every week is in the passive voice; its counterpart in the active voice would require the addition of an agent, as in Joe cleans the floors every week. In English, the passive voice requires a form of the verb to be, such as is or was, and a verb in its passive participle form, such as cleaned.

Phonological: Pertaining to the sounds of words and how they relate to the sound-systems and tendencies of a particular language (i.e. phonology)

Possessive: A possessive construction involves two noun phrases that stand in a particular relation with one another, such as ownership (Mary's bike), kinship (Mary's sister), creation (Mary's article), and part-whole (Mary's finger), among others. A possessive pronoun is a pronoun that stands in for the possessor noun phrase, such as her in her bike/sister/article/finger/etc.

Predicate: A predicate is a noun phrase, adjective phrase, verb phrase or prepositional phrase that is used to say something about the subject of the sentence. For example, in the sentences My mom is a judge, My mom is smart, My mom works hard, and My mom is in court, the subject is my mom and the bolded phrases are predicates.

Predicate position: The position, generally following be, seems, or similar verbs, where noun phrases, adjective phrases and prepositional phrases function as predicates. This term is commonly used to describe the position of adjectives in sentences like The book is red. This contrasts with “attributive position,” where an adjective modifies a noun as part of a noun phrase (as in the red book).

Preposition: Words like to, in or with that combine with a noun, forming a prepositional phrase that often indicates location, time, direction or various grammatical meanings. For example, in the sentence I went to school, to is a preposition and to school is a prepositional phrase that indicates a direction. In I gave the book to my sister, to is a preposition and to my sister is a prepositional phrase that indicates who received the book.

Pseudocleft: A construction similar to a cleft that begins with a wh-word rather than it. As in a cleft, the wh-word is followed by a form of be and then information that the speaker is trying to highlight. For example, the sentence What I ate was a hotdog draws attention to what was eaten (the hotdog); the fact that eating occurred is not emphasized. Unlike in a cleft, in a pseudocleft the important information appears at the end of the sentence, rather than immediately following be.

Psych-verb: A psychological verb, or psych-verb, is a verb that expresses a mental and/or emotional state (or event). For example, in a sentence like Mary's behavior angers me, the psych-verb anger expresses the emotional state of the object (me). In a sentence like Mary loves her pet turtle, the psych-verb love expresses the emotional state of the subject (Mary). When the object's emotional state is expressed, the subject is sometimes volitional (as in Mary is bothering me on purpose) and sometimes non-volitional (as in That news really bothered me).

Quasimodal: A word or phrase, such as need to, able to, supposed to, or better that has features similar to those of modals but is not a true modal (see glossary entry herein). Quasimodals express possibility, necessity or ability, like modals. However, they cannot take contracted negation (n’t) or undergo subject-auxiliary inversion.

Relative: A relative clause is a type of embedded clause that modifies a noun phrase directly, such as the underlined clauses in the student who I tutored, the student who called, the book that you read, the person you saw, or the tool which you used.

Semantics: In linguistics, semantics is the study of meaning at a word-, phrase-, and sentence-level. One aspect of semantics studies how interlocutors understand sentences from the meanings of the words and phrases involved. For example, the sentence #Lola is a cat, and Lola is not a cat has proper syntax, but semantics tells us that it doesn't make sense because it contains a direct contradiction. Another aspect of semantics studies how words are allowed to combine based on their meanings. For example, certain verbs must have an animate subject, hence the strangeness of a sentence like #The book slept all day, which also has proper syntax but fails to abide by the semantic constraints of the English verb sleep.

Stative: A verb that refers to a state of being rather than an action. For example, the verb know in We know French is stative, while the verb learn in We learn French is not. Stative verbs typically cannot appear in the progressive: *I am knowing French is unacceptable for this reason. However, I am learning French, which uses the eventive verb learn, is perfectly acceptable. Some verbs can have both stative and non-stative (eventive) interpretations. For example, smell can be stative (The flowers smell good) or eventive (I smell something rotten in the fridge).

Stress: A property of a syllable or word that gives it relative emphasis over other syllables or words. Stress can manifest through such parameters as volume, pitch, and duration of speech. Stress is often denoted with capitalized letters. In English, for example, nouns tend to have stress on the first syllable as in SOfa, ICEcream, PENcil. Syllables and words may be said to be "stressed," "unstressed," or have "partial/secondary stress."

Superlative: Referring to an adjective that denotes the utmost degree of a given quality. For example, in the scale of good - better - best, best is the superlative adjective. Superlatives are often marked in English with the suffix -est or through combination with the adverb most, as in smartest or most intelligent.

Syntax: The way words combine to form phrases and sentences that have meaning. Syntax studies the rules that dictate the order in which words can be strung together, and, to look at it from the other direction, the positions that different types of words are allowed to occupy. For example, English syntax mandates a Subject-Verb-Object word order, meaning that a sentence like Lucy loves rain is syntactically well-formed, while a sentence like Lucy rain loves is not.

Tag question: A question added at the end of a statement that invites the addressee to confirm or disconfirm the content of the statement. For example, the sentences It’s cold outside, isn’t it? and She looks lovely, doesn’t she? have the tag questions isn’t it? and doesn’t she?, respectively.

Tense: A grammatical feature pertaining to the position of an event in time with respect to the moment of uttering. In English, verbs can function as the main verb of an independent clause if they have "finite" tense, i.e. Past, Present, or Future; however, verbs can also have "non-finite" tense in such forms as infinitives (to VERB) and gerunds (VERBing).

Theme: An entity whose state or position is changed or specified by the verb. For example, in the sentence I ate a cake, the noun phrase a cake is the theme of the verb ate.

Transitive verb: A verb that can take a direct object. For example, in the sentence I love dogs, the verb love is transitive and takes the direct object dogs.

Verbal particle: Words like out and up that often resemble prepositions but function as part of a verb. For example, in phrasal verbs like hand out and get up, out and up are verbal particles. Verbal particles can be distinguished from prepositions in several ways. First, verbal particles allow objects to appear either to their right (as in Hand out the papers) or left (as in Hand the papers out). Prepositions only allow their objects to their right (as in Look out the window), but not to their left (as in *Look the window out). Second, prepositions can move as a chunk with their objects (as in It was out the window that they looked), while verbal particles cannot (as in *It was out the papers that they handed). Out, then, is a preposition in look out but a verbal particle in hand out.

Volitional: A noun or noun phrase is volitional if it refers to someone who is acting according to their own desires or will. For example, in the sentence Brutus murdered Julius Caesar, the subject Brutus is volitional, while in the sentence The hurricane killed many people, the subject the hurricane is non-volitional. Verbs are sometimes called volitional verbs when they occur with or require volitional noun phrases.

VP-ellipsis: VP stands for Verb Phrase, and VP-ellipsis is when a previously mentioned verb phrase is left implicit. For example, in the sentence I might go to the store and he might [go to the store] too, the second instance of go to the store does not need to be included and can be left out. The version of the sentence with VP-ellipsis is I might go to the store and he might, too.

Well-formed: Acceptable to a native speaker in terms of its grammar and/or its meaning. For example, the sentence I like dogs is well-formed because it is judged grammatical by native speakers and conveys a meaning that makes sense. Meanwhile, the sentence Green ideas sleep is ill-formed in terms of its meaning, but well-formed in terms of its grammar.