606. A Complex Sentence consists of a principal sentence and one or more subordinate sentences, which are then called clauses.
b. A Subordinate clause is marked
1. Always by an introductory subordinating word;
2. Often by a change of mode;
3. Sometimes by a change of person, in verb and pronoun;
4. Sometimes by a change of tense; but only in the indicative, from present to imperfect or from perfect to pluperfect.1
c. A direct quotation, or an indirect question that retains the direct form, though clearly subordinate, can hardly be separated from cases of parataxis (§ 604).
609. Three functions, in the following order of development, may belong to a subordinating word:
1. It has its own construction in the subordinate clause, as adverb, pronoun, or adjective.
2. It connects the subordinate clause with some word, expressed or implied, in the leading clause.
3. Both these functions fall into the background, and one or both may disappear, as the subordinating word comes more distinctly to denote the relation of clause to clause, rather than of word to word.
- 1In English, change of order is often the only sign of subordination; so sometimes change of tense.