B3-e: Subordinate clauses
Subordinate clauses are patterned like sentences, having subjects and verbs and sometimes objects or complements. But they function within sentences as adjectives, adverbs, or nouns. They cannot stand alone as complete sentences.
A subordinate clause usually begins with a subordinating conjunction or a relative pronoun. The chart below classifies these words according to the kinds of clauses (adjective, adverb, or noun) they introduce.
Adjective clauses
Adjective clauses modify nouns or pronouns, usually answering the question Which one? or What kind of ? Most adjective clauses begin with a relative pronoun (who, whom, whose, which, or that). In addition to introducing the clause, the relative pronoun points back to the noun that the clause modifies.
Relative pronouns are sometimes “understood.”
The things [that] we cherish most are the things [that] we might lose.
Occasionally an adjective clause is introduced by a relative adverb, usually when, where, or why.
The parts of an adjective clause are often arranged as in sentences (subject/verb/object or complement).
Frequently, however, the object or complement appears first, out of the normal order of subject/verb/object.
tip: For punctuation of adjective clauses, see P1-e and P2-e. For advice about avoiding repeated words in adjective clauses, see M3-d.
Adverb clauses
Adverb clauses modify verbs, adjectives, or other adverbs, usually answering one of these questions: When? Where? Why? How? Under what conditions? To what degree? They always begin with a subordinating conjunction (such as after, although, because, that, though, unless, or when). (For a complete list, see the chart below.)
Noun clauses
A noun clause functions just like a single-word noun, usually as a subject, a subject complement, a direct object, or an object of a preposition. It usually begins with one of the following words: how, if, that, what, whatever, when, where, whether, which, who, whoever, whom, whomever, whose, why. (For a complete list, see the chart below.)
The subordinating word introducing the clause may or may not play a significant role in the clause. In the preceding examples, Whoever is the subject of its clause, but that does not perform a function in its clause.
As with adjective clauses, the parts of a noun clause may appear in normal order (subject/verb/object or complement) or out of their normal order.
Words that introduce subordinate clauses
Words introducing adjective clauses
relative pronouns: that, which, who, whom, whose
relative adverbs: when, where, why
Words introducing adverb clauses
subordinating conjunctions: after, although, as, as if, because, before, even though, if, in order that, since, so that, than, that, though, unless, until, when, where, whether, while
Words introducing noun clauses
relative pronouns: which, who, whom, whose
other pronouns: what, whatever, whichever, whoever, whomever
other subordinating words: how, if, that, when, whenever, where, wherever, whether, why