Subordinate clause

A dependent clause is a clause that provides an independent clause with additional information, but which cannot stand alone as a sentence. Dependent clauses either modify the independent clause of a sentence or serve as a component of it. Some grammarians use the term subordinate clause as a synonym for dependent clause. Others use subordinate clause to refer only to adverbial dependent clauses.

The different types of dependent clauses include noun clauses, relative (adjectival) clauses, and adverbial clauses.

In Indo-European languages, a dependent clause usually begins with a dependent word. One kind of dependent word is a subordinating conjunction. Subordinating conjunctions are used to begin dependent clauses known as adverbial clauses, which serve as adverbs. In the following examples, the adverbial clauses are bold and the subordinating conjunctions are italicized:

A subordinating conjunction can also introduce a noun clause:

Another type of dependent word is the relative pronoun. Relative pronouns begin dependent clauses known as relative clauses; these are adjective clauses, because they modify nouns. In the following example, the relative clause is bold and the relative pronoun is italicized:

A relative adverb plays the role of an adverb in a relative clause, as in

An interrogative word can serve as an adverb in a noun clause, as in

A content clause, also known as a "noun clause", provides content implied or commented upon by its main clause. It can be a subject, predicate nominative, direct object, appositive, indirect object, or object of the preposition. Some of the English words that introduce content clauses are that, whether, who, why, whom, what, how, when, whoever, where, and whomever. Notice that some of these words also introduce relative and adverbial clauses. A clause is a content clause if a pronoun (he, she, it, or they) could be substituted for it. Follow these examples:

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