The sentence is above all a communicative unit; therefore, the primary classification of sentences is based on the communicative principle, traditionally defined as “the purpose of communication”. According to the purpose of communication, sentences are subdivided into declarative, interrogative and imperative. Declarative sentences are traditionally defined as those expressing statements, either affirmative or negative, e.g.: He (didn’t) shut the window. Imperative sentences express inducements of various kinds (orders or requests); they may also be either affirmative or negative, e.g.: (Don’t) Shut the window, please. Interrogative sentences express questions, or requests for information, e.g.: Did he shut the window?
There have been attempts to refute this traditional classification of communicative sentence types and to introduce a new one. For example, Charles Fries suggested classifying all the utterances not on the basis of their own semantics, but on the kind of responses which they elicit, or according to their external characteristics. He distinguished, first, utterances which are followed by oral responses (greetings, calls, questions, etc.); second, utterances followed by action responses (requests or commands); and third, utterances which elicit signals of attention to further conversation (statements); additionally, he distinguished a minor group of utterances, which are not directed to any interlocutor in particular and presuppose no response (“non-communicative utterances”, e.g., interjectional outcries).
Fries’s classification does not refute the traditional classification of communicative sentence types, but rather confirms and specifies it: the purpose of communication inherent in the addressing sentence is reflected in the listener’s response. Therefore, the two approaches can be combined in the descriptions of each type of sentence according to their inner and outer communicative features: declarative sentences are defined as sentences which express statements and can be syntagmatically connected with the listener’s signals of attention (his or her appraisal, agreement, disagreement, etc.), e.g.: He didn’t shut the window. - Oh, really?; imperative sentences express inducements, situationally connected with the listener’s actions or verbal agreement/disagreement to perform these actions, e.g.: Shut the window, please. – OK, I will; interrogative sentences express requests for information and are syntagmatically connected with answers, e.g.: Did he shut the window? – Yes, he did. The other types utterances distinguished by Fries are minor intermediary communicative types of sentences: greetings make up the periphery of the declarative sentence type as statements of good will at meeting and parting; calls can be treated as the periphery of the inducement sentence type, as requests for attention; “non-communicative” utterances are excluded from the general category of the sentence as such, because they lack major constituent features of sentences (see Unit 23).
Further distinctions between the three cardinal types of sentences may be revealed in the light of the actual division of the sentence: each communicative sentence type is distinguished by its specific actual division features, especially, the nature of the rheme.
The strictly declarative sentence immediately expresses a certain proposition, and the actual division of the declarative sentence presents itself in the most developed and complete form: the rheme of the declarative sentence provides the immediate information that constitutes the informative center of the sentence in opposition with its thematic part, e.g.: He (theme) shut the window (rheme).
The strictly imperative sentence does not express any statement of fact, i.e. any proposition proper. It is only based on a proposition, without formulating it directly, e.g.: Let him shut the window (He hasn’t shut the window). Thus, the rheme of the imperative sentence expresses the informative nucleus notof an explicit proposition, but of an inducement, an action wanted, required, necessary, etc. (or, unwanted, unnecessary, etc.). Due to the communicative nature of the inducement addressed to the listener, the theme of the imperative sentence may be omitted or may take the form of an address, e.g.: Shut the window, please; Tom, shut the window.
The rheme of the interrogative sentence is informationally open: it is an informative gap, which is to be filled by the answer. This rhematic “zero” in pronominal (“special”) questions is expressed by an interrogative pronoun, which is substituted by the actual information wanted in the answer, e.g.: Who shut the window? – Tom (did). The interrogative pronoun in the question and the rheme of the answer make up the rhematic unity in the question-answer construction. The openness of the rheme in non-pronominal questions consists in the alternative semantic suggestions from which the listener has to choose the appropriate one. The semantic choice is explicit in the structure of alternative questions, e.g.: Did he or his friend shut the window? The rheme of non-pronominal questions requiring either confirmation or negation (“general” question of yes-no response type) is implicitly alternative, implying the choice between the existence or non-existence of an indicated fact (true to life or not true to life?), e.g.: Did he shut the window? – Yes, he did (No, he didn’t). The thematic part of the answer, being expressed in the question, is easily omitted, fully or partially, as the examples show.
Traditionally, the so-called exclamatory sentence is distinguished as one more communicative type of sentence. Exclamatory sentences are marked by specific intonation patterns (represented by an exclamation mark in written speech), word-order and special constructions with functional-auxiliary words, rendering the high emotional intensity of the utterance. But these regular grammatical features can not be treated as sufficient grounds for placing the exclamatory sentences on the same level as the three cardinal communicative types of sentences. In fact, each cardinal communicative type, declarative, imperative or interrogative, may be represented in its exclamatory, emotionally coloured variant, as opposed to a non-exclamatory, unemotional variant, cf.: She is a nice little girl – What a nice little girl she is!; Open the door. – For God’s sake, open the door!; Why are you late? – Why on earth are you late?! Exclamation is actually an accompanying feature of the three cardinal communicative types of sentences, which discriminates emotionally intense constructions from emotionally neutral ones at the lower level of analysis, but it does not constitute a separate communicative type.
As for so-called “purely exclamatory sentences”, such as My God!; Goodness gracious!; etc., as was mentioned earlier, they are not sentences in the proper sense of the term: though they occupy isolated positions like separate utterances in speech and resemble regular sentences in written representation, these interjection-type outcries do not render any situational nomination or predication and they possess no informative perspective. They can be defined as “non-sentential utterances” which serve as symptoms of emotional reactions; they are also treated as “pseudo-sentences”, “sentence-substitutes” or “non-communicative utterances” (according to Ch. Fries).
Besides the three cardinal monofunctional communicative types of sentences, there is a number of constructional sentence models of intermediary, mixed communicative character. The transfer of certain communicative features from one communicative type of sentence to another can be observed in correlations of all three cardinal communicative types, i.e. in statement – question, statement – inducement, and inducement – question correlations.
So-called indirect questions have the form of a declarative sentence, but actually express a request for information, e.g.: I wonder who shut the window (cf.: Who shut the window?). An answer is expected, as with a regular question, e.g.: I wonder who shut the window. – Tom did; the response supports the mixed communicative character of this sentence type. Sentences of this type, declarative in form and intermediary between statements and questions in meaning, render the connotation of insistence in asking for information. On the other hand, so-called rhetorical questions are interrogative in their structural form, but express a declarative functional meaning of high intensity, e.g.: How can you say a thing like this? The sentence does not express a question; it is a reprimand. No answer is expected; the responses elicited by rhetorical questions correspond to responses elicited by declarative sentences (signals of attention, appraisals, expressions of feelings, etc.), e.g.: How can you say a thing like this? – Oh, I’m terribly sorry, I did not mean it. If a direct answer follows the rhetorical question, it emphasizes implications opposite to the content of the question; often it is the speaker himself or herself, who answers the rhetorical question, e.g.: Who is to be blamed for it? No one, but myself.
Intermediary between statements and inducements are formally declarative sentences with modal verbs and other lexical means of inducement, e.g.: You must shut the window; I want you to shut the window (cf.: Shut the window, please!). The responses to these sentences are similar to those elicited by imperative sentences proper, i.e. actional responses or verbal agreement or disagreement to perform the actions, e.g.: I want you to shut the window. - O.K., I will. On the other hand, inducive constructions can be used to express a declarative meaning of high expressiveness and intensity, in particular, in various proverbs and maxims, e.g.: Scratch my back, and I’ll scratch yours (= One good turn deserves another). They presuppose no actional response.
Inducive constructions can also be used to express a request for information, inducing the listener to verbal response of information rendering; they represent another type of indirect question, e.g.: Tell me who shut the window (ñf.: Who shut the window?) The reverse intermediary construction, that of inducement in the form of a question, is very characteristic of English; it is employed to convey various shades of politeness, suggestion, softening of a command, etc., e.g.: Will you, please, shut the window? Could you shut the window, please? The response elicited by such polite requests resembles the one to a proper inducement, e.g.: Will you, please, shut the window? - O.K., I will.
Thus, the classification of the communicative sentence types, in addition to three cardinal communicative types, includes six intermediary subtypes of sentences of mixed communicative features; first, mixed sentence patterns of declaration (interrogative-declarative, imperative-declarative), second, mixed sentence patterns of interrogation (declarative-interrogative, imperative-interrogative), and, third, mixed sentence patterns of inducement (declarative-imperative, interrogative-imperative). Most of the intermediary communicative types of sentences perform distinct stylistic functions, and can be treated as cases of transposition of the communicative types of sentences presented in oppositions, paradigmatically (see Unit 24).
The communicative description of utterances was undertaken at the end of the 1960s by J. R. Searle within the framework of the so-called “theory of speech acts”, on the basis of philosophical ideas formulated by J. L. Austin. Utterances are interpreted as actions or acts by which the speaker does something (the title of the book by J. L. Austin was How to Do Things with Words). On the basis of various communicative intentions of the speaker, J. R. Searle produced a detailed classification of so-called pragmatic (i.e. pertaining to the participants and the circumstances of the particular speech act) utterance types. The two basic utterance types are defined as performatives and constatives (representatives): performatives are treated as utterances by which the speaker explicitly performs a certain act, e.g.: I surrender; I pronounce you husband and wife; and constatives (representatives) as utterances by which the speaker states something, e.g.: I am a teacher; constatives are further subdivided into minor types, such as promissives (commissives), e.g.: I will help you; expressives, e.g.: How very sad!; menacives, e.g.: I’ll kill you!, directives, e.g.: Get out!; requestives, e.g.: Bring the chalk, please; etc. From the purely linguistic point of view, various speech acts correlate structurally and functionally with the three cardinal communicative types of sentences. The mixed communicative types of sentences can be interpreted in the theory of speech acts as indirect speech acts, e.g.: ‘There is no chalk left’ may be interpreted as a representative or as a directive: There is no chalk left (= bring some more); ‘I’ll be watching you!’ under different communicative circumstances may be either a constative, a promissive or even a menacive.
Later the theory of speech acts developed into a separate branch of linguistics known as “pragmatic linguistics” (“pragmalinguistics”, or “pragmatics”); this approach is used in syntactic studies as complementary to the classification of the grammatically distinguished communicative types of sentences.