14) Classification of subord clauses

Subordinate clauses are classified on two mutually complementary bases: on the functional principle and on the categorial principle. According to the functional principle they are divided on the analogy (though, not identity) of the positional parts of the simple sentence that underlies the structure of the complex sentence. E.g.: What you see is what you get. - What you see (the subject, the subject subordinate clause) is what you get (the object, the object subordinate clause). According to the categorial principle, subordinate clauses are divided by their inherent nominative properties; there is certain similarity (but, again, not identity) with the part-of-speech classification of words. Subordinate clauses can be divided into three categorial-semantic groups: substantive-nominal, qualification-nominal and adverbial. Substantive-nominal subordinate clauses name an event as a certain fact, e.g.: What you do is very important; cf.: What is very important? Qualification-nominal subordinate clauses name a certain event, which is referred, as a characteristic to some substance, represented either by a word or by another clause, e.g.: Where is the letter that came today?; cf.: What letter? Adverbial subordinate clauses name a certain event, which is referred, as a characteristic to another event, to a process or a quality, e.g.: I won’t leave until you come. The two principles of subordinate clause classification are mutually complementary: the categorial features of clauses go together with their functional sentence-part features similar to the categorial features of words going together with their functional characteristics. Thus, subordinate clauses are to be classified into three groups: first, clauses of primary nominal positions, including subject, predicative and object clauses; second, clauses of secondary nominal positions, including various attributive clauses; and third, clauses of adverbial positions. Clauses of primary nominal positions, including subject, predicative and object clauses, are interchangeable with each other, cf.: What you see is what you get; What you get is what you see; You’ll be surprised at what you see. The subject clause regularly expresses the theme of a complex sentence, and the predicative clause regularly expresses its rheme. The subject clause may express the rheme of the sentence, if it is introduced by the anticipatory ‘it’, e.g.: It is true that he stole the jewels. The subject clause in such complex sentences is at the same time appositive. The status of the object clause is most obvious in its prepositional introduction (as in the example above). Sometimes it is mixed with other functional semantics, determined by the connectors, in particular, with adverbial relational meanings, e.g.: Do you know when they are coming? A separate group of object clauses are those presenting the chunks of speech and mental activity processes, traditionally discussed under the heading “the rules of reported speech”, e.g.: She said she would come early; Do you mean you like it?