In language, a clause is a constituent or phrase that comprises a semantic predicand (expressed or not) and a semantic predicate. A typical clause consists of a subject and a syntactic predicate,For a definition of the clause that emphasizes the subject-predicate relationship, see Radford (2004327f.). the latter typically a verb phrase composed of a verb with or without any objects and other modifiers. However, the subject is sometimes unexpressed if it is easily deducible from the context, especially in null-subject languages but also in other languages, including instances of the imperative mood in English.
A complete simple sentence contains a single clause with a finite verb. Complex sentences contain at least one clause subordinated to (dependent on) an independent clause (one that could stand alone as a simple sentence), which may be co-ordinated with other independents with or without dependents. Some dependent clauses are non-finite, i.e. they do not contain any element/verb marking a specific tense.
Matrix clauses A clause that contains one or more dependent or subordinate clauses is called a . A matrix clause can be the main clause or any subordinate clause that itself contains one or more (additional) subordinate clauses.
Major distinctions A primary division for the discussion of clauses is the distinction between independent clauses and dependent clauses.Most basic discussions of the clause emphasize the distinction between main and subordinate clauses. See for instance Crystal (1997:62). An independent clause can stand alone, i.e. it can constitute a complete sentence by itself. A dependent clause, by contrast, relies on an independent clause's presence to be efficiently utilizable.
A second significant distinction concerns the difference between finite and non-finite clauses. A finite clause contains a structurally central finite verb, whereas the structurally central word of a non-finite clause is often a non-finite verb. Traditional grammar focuses on finite clauses, the awareness of non-finite clauses having arisen much later in connection with the modern study of syntax. The discussion here also focuses on finite clauses, although some aspects of non-finite clauses are considered further below.
Clauses can be classified according to a distinctive trait that is a prominent characteristic of their syntactic form. The position of the finite verb is one major trait used for classification, and the appearance of a specific type of focusing word (e.g. Wh-word) is another. These two criteria overlap to an extent, which means that often no single aspect of syntactic form is always decisive in deciding how the clause functions. There are, however, strong tendencies.
Standard SV-clauses Standard SV-clauses (subject-verb) are the norm in English. They are usually declarative (as opposed to exclamative, imperative, or interrogative); they express information neutrally, e.g.
The pig has not yet been fed. Declarative clause, standard SV order I've been hungry for two hours. Declarative clause, standard SV order ...that I've been hungry for two hours. Declarative clause, standard SV order, but functioning as a subordinate clause due to the appearance of the subordinator that
Declarative clauses like these are by far the most frequently occurring type of clause in any language. They can be viewed as basic, with other clause types being derived from them. Standard SV-clauses can also be interrogative or exclamative, however, given the appropriate intonation contour and/or the appearance of a question word, e.g.
a. The pig has not yet been fed? Rising intonation on fed makes the clause a yes/no question.
b. The pig has not yet been fed! Spoken forcefully, this clause is exclamative.
c. You've been hungry for how long? Appearance of interrogative word how and rising intonation make the clause a constituent question
Examples like these demonstrate that how a clause functions cannot be known based entirely on a single distinctive syntactic criterion. SV-clauses are usually declarative, but intonation and/or the appearance of a question word can render them interrogative or exclamative.
Verb first clauses Verb first clauses in English usually play one of three roles: 1. They express a yes/no-question via subject–auxiliary inversion, 2. they express a condition as an embedded clause, or 3. they express a command via imperative mood, e.g.
a. He must stop laughing. Standard declarative SV-clause (verb second order) b. Should he stop laughing? Yes/no-question expressed by verb first order c. Had he stopped laughing, ... Condition expressed by verb first order d. Stop laughing! Imperative formed with verb first order
a. They have done the job. Standard declarative SV-clause (verb second order) b. Have they done the job? Yes/no-question expressed by verb first order c. Had they done the job, ... Condition expressed by verb first order d. Do the job! Imperative formed with verb first order
Most verb first clauses are independent clauses. Verb first conditional clauses, however, must be classified as embedded clauses because they cannot stand alone.
Wh-clauses In English, Wh-clauses contain a wh-word. Wh-words often serve to help express a constituent question. They are also prevalent, though, as relative pronouns, in which case they serve to introduce a relative clause and are not part of a question. The wh-word focuses a particular constituent, and most of the time, it appears in clause-initial position. The following examples illustrate standard interrogative wh-clauses. The b-sentences are direct questions (independent clauses), and the c-sentences contain the corresponding indirect questions (embedded clauses):
a. Sam likes the meat. Standard declarative SV-clause b. Who likes the meat? Matrix interrogative wh-clause focusing on the subject c. They asked who likes the meat. Embedded interrogative wh-clause focusing on the subject
a. Larry sent Susan to the store. Standard declarative SV-clause b. Whom did Larry send to the store? Matrix interrogative wh-clause focusing on the object, subject-auxiliary inversion present c. We know whom Larry sent to the store. Embedded wh-clause focusing on the object, subject-auxiliary inversion absent
a. Larry sent Susan to the store. Standard declarative SV-clause b. Where did Larry send Susan? Matrix interrogative wh-clause focusing on the oblique object, subject-auxiliary inversion present c. Someone is wondering where Larry sent Susan. Embedded wh-clause focusing on the oblique object, subject-auxiliary inversion absent
One important aspect of matrix wh-clauses is that subject-auxiliary inversion is obligatory when something other than the subject is focused. When it is the subject (or something embedded in the subject) that is focused, however, subject-auxiliary inversion does not occur.
a. Who called you? Subject focused, no subject-auxiliary inversion b. Whom did you call? Object focused, subject-auxiliary inversion occurs
Another important aspect of wh-clauses concerns the absence of subject-auxiliary inversion in embedded clauses, as illustrated in the c-examples just produced. Subject-auxiliary inversion is obligatory in matrix clauses when something other than the subject is focused, but it never occurs in embedded clauses regardless of the constituent that is focused. A systematic distinction in word order emerges across matrix wh-clauses, which can have VS order, and embedded wh-clauses, which always maintain SV order, e.g.
a. Why are they doing that? Subject-auxiliary inversion results in VS order in matrix wh-clause. b. They told us why they are doing that. Subject-auxiliary inversion is absent in embedded wh-clause. c. *They told us why are they doing that. Subject-auxiliary inversion is blocked in embedded wh-clause.
a. Whom is he trying to avoid? Subject-auxiliary inversion results in VS order in matrix wh-clause. b. We know whom he is trying to avoid. Subject-auxiliary inversion is absent in embedded wh-clause. c. *We know whom is he trying to avoid. Subject-auxiliary inversion is blocked in embedded wh-clause.
Relative clauses
Relative clauses are a mixed group. In English they can be standard SV-clauses if they are introduced by that or lack a relative pronoun entirely, or they can be wh-clauses if they are introduced by a wh-word that serves as a relative pronoun.
Clauses according to semantic predicate-argument function Embedded clauses can be categorized according to their syntactic function in terms of predicate-argument structures. They can function as arguments, as adjuncts, or as predicative expressions. That is, embedded clauses can be an argument of a predicate, an adjunct on a predicate, or (part of) the predicate itself. The predicate in question is usually the predicate of an independent clause, but embedding of predicates is also frequent.
Argument clauses A clause that functions as the argument of a given predicate is known as an argument clause. Argument clauses can appear as subjects, as objects, and as obliques. They can also modify a noun predicate, in which case they are known as content clauses.
That they actually helped was really appreciated. SV-clause functioning as the subject argument They mentioned that they had actually helped. SV-clause functioning as the object argument
What he said was ridiculous. Wh-clause functioning as the subject argument We know what he said. Wh-clause functioning as an object argument He talked about what he had said. Wh-clause functioning as an oblique object argument
The following examples illustrate argument clauses that provide the content of a noun. Such argument clauses are content clauses:
a. the claim that he was going to change it Argument clause that provides the content of a noun (i.e. content clause) b. the claim that he expressed Adjunct clause (relative clause) that modifies a noun
a. the idea that we should alter the law Argument clause that provides the content of a noun (i.e. content clause) b. the idea that came up Adjunct clause (relative clause) that modifies a noun
The content clauses like these in the a-sentences are arguments. Relative clauses introduced by the relative pronoun that as in the b-clauses here have an outward appearance that is closely similar to that of content clauses. The relative clauses are adjuncts, however, not arguments.
Adjunct clauses Adjunct clauses are embedded clauses that modify an entire predicate-argument structure. All clause types (SV-, verb first, wh-) can function as adjuncts, although the stereotypical adjunct clause is SV and introduced by a subordinator (i.e. subordinate conjunction, e.g. after, because, before, now, etc.), e.g.
a. Fred arrived before you did. Adjunct clause modifying matrix clause b. After Fred arrived, the party started. Adjunct clause modifying matrix clause c. Susan skipped the meal because she is fasting. Adjunct clause modifying matrix clause
These adjunct clauses modify the entire matrix clause. Thus before you did in the first example modifies the matrix clause Fred arrived. Adjunct clauses can also modify a nominal predicate. The typical instance of this type of adjunct is a relative clause, e.g.
a. We like the music that you brought. Relative clause functioning as an adjunct that modifies the noun music b. The people who brought music were singing loudly. Relative clause functioning as an adjunct that modifies the noun people c. They are waiting for some food that will not come. Relative clause functioning as an adjunct that modifies the noun food
Predicative clauses An embedded clause can also function as a predicative expression. That is, it can form (part of) the predicate of a greater clause.
a. That was when they laughed. Predicative SV-clause, i.e. a clause that functions as (part of) the main predicate b. He became what he always wanted to be. Predicative wh-clause, i.e. wh-clause that functions as (part of) the main predicate