Inlinguistics, adependent clause(or asubordinate clause) is aclausethat augments anindependent clausewith additional information, but which cannot stand alone as asentence. Dependent clauses eithermodify the independent clause of a sentence or serve as a component of it. Some grammarians use the termsubordinate clauseas a synonym fordependent clause.Other grammars usesubordinate clauseto refer only to adverbial dependent clauses. There are also different types of dependent clauses, including noun clauses, relative (adjectival) clauses, and adverbial clauses.Dependent wordsInIndo-European languages, a dependent clause usually begins with a dependent word. One kind ofdependent word is asubordinating conjunction. Subordinating conjunctions are used to begin dependent clauses known asadverbial clauses, which act likeadverbs. In the following examples,the adverbial clauses are bold and the subordinating conjunctions are italicized:*.Wherevershegoes, she leaves anitem of luggage behind.(The adverbial clausewherever she goesmodifies theverbleaves.)*.Bob enjoyed the movie morethanI did.(The adverbial clausethan I didmodifies the adverbmore.)A subordinating conjunction can also introduce anoun clause:*.I knowthathe likes me.(The noun clausethathe likes meserves as the object of the main-clause verbknow.)Another type of dependent word is therelative pronoun. Relative pronouns begin dependent clauses known asrelative clauses; these areadjective clauses, because they modifynouns. In the following example, the relative clause is bold and the relative pronoun is italicized:*.The only one of the seven dwarfswhodoes not have a beardis Dopey.(The adjective clausewhodoes not have a bearddescribes the pronounone.)A relative adverb plays the role of an adverb in a relative clause, as in*.That is the reasonwhyI came.(The relative clausewhyI camedescribes the nounreason, and within the relative clause the adverbwhymodifies the verbcame.)*.That is the placewherehe lives.(The relative clausewherehe livesdescribes the nounplace, and within the relative clause the adverbwheremodifies the verblives.)Aninterrogative wordcan serve as an adverb in a noun clause, as in*.No one understandswhyyou need experience.(The noun clausewhyyou need experiencefunctions as thedirect objectof the main-clause verb"understands", and within the noun clausewhyserves as an adverb modifyingneed.)Noun clauseA noun clause can be used like a noun. It can be asubject,predicate nominative,direct object,appositive,indirect object, or object of thepreposition. Some of the English words that introduce noun clauses arethat, whether, who, why, whom, what, how, when, whoever, where,andwhomever. Notice that some of these words also introduce adjective and adverbial clauses. A clause is a noun clause if a pronoun (he, she, it, or they) could be substituted for it.Examples:*.I knowwho said that. (I know him/her.) (The dependent clause serves as the object of the main-clause verb "know".)*.Whoever made that assertionis wrong. (He/she is wrong.) (The dependent clause serves as the subject of the main clause.)Sometimes in English a noun clauseis used without the introductory word.Example:*.I knowthat he is here.*.I knowhe is here. (without "that")In some cases, use of the introductory word, though grammatically correct, may sound cumbersome in English, and the introductory word may be omitted.Example:*.I thinkthat it is pretty. (less common)*.I thinkit is pretty. (more common)Relative (adjectival) clauseIn Indo-European languages, a relative clause, also called an adjective clause or an adjectival clause, will meet three requirements:1.Like all dependent clauses, it will contain a verb (and it will also contain a subject unless it is anon-finite dependent clause). However, in apro-drop languagethe subject may be azero pronoun—that is, the pronoun may not be explicitly included because its identity is conveyed bya verbalinflection.2.It will begin with a relative adverb [when, where,orwhyin English] or a relative pronoun [who, whom, whose, that,orwhichin English]. However, the English relative pronoun may be omitted and only implied if it plays the role of the object of the verb or object of a preposition in a restrictive clause; for example,Heis the boy I sawis equivalent toHeis the boy whom I saw, andI saw the boy you are talking aboutis equivalent to the more formalI saw the boy about whom you are talking.3.The relative clause will function asan adjective, answering questions such as "what kind?", "how many?" or "which one?".The adjective clause in English will follow one of these patterns:*.Relative Pronoun [Functioning as Object of Verb] + Subject + VerbThis is the ballthatI was bouncing.*.Relative Adverb + Subject + Verb (possibly + Object of Verb)That is the housewhereI grew up.That is the housewhere I met her.*.Relative Pronoun [Functioning as Subject] + Verb (possibly + Object of Verb)That is the personwhohiccuped.That is the personwhosaw me.*.Relative Pronoun [Functioning as Object of Preposition] + Subject + Verb (possibly + Object of Verb) + PrepositionThat is the personwho(m)I was talking about.That is the personwho(m)I was telling you about.*.Preposition + Relative Pronoun [Functioning as Object of Preposition] + Subject + Verb (possibly + Object of Verb)That is the personaboutwhomI was talking.That is the personaboutwhomI was telling you.*.Possessive Relative Pronoun + Noun [Functioning as Subject] + Verb (possibly + Object of Verb)That is the dogwhosebig brown eyes pleaded for another cookie.That is the dogwhosebig brown eyes begged me for another cookie.*.Possessive Relative Pronoun + Noun [Functioning as Object of Verb] + Subject + VerbThat is the personwhosecar I saw.For a discussion of adjective clauses in languages other than English, seeRelative clause#Examples.PunctuationEnglish punctuationThe punctuation of an adjective clause depends on whether it is essential or nonessential and use commas accordingly. Essential clauses are not set off with commas, while non-essential clauses are. An adjective clause is essential if the information it contains is necessary to the meaning of the sentence. For example:*.The vegetablesthat people often leave uneatenare usually the most nutritious.Here "vegetables" is nonspecific. Accordingly, in order to know whichones is being referred to, one must have the information provided in the adjective clause (in italics). Because it restricts the meaning of"vegetable", this adjective clause is called a restrictive clause. It is essential to the meaning of the main clause and uses no commas (and correspondingly, does not experience a pause when spoken).However, if the additional information does not help to identify more narrowly the identity of the noun antecedent but rather simply provides further informationabout it, then the adjective clause isnon-restrictive and does require commas (or a spoken pause) to separate it from the rest of the sentence. For example:*.Broccoli,which people often leaveuneaten, is very nutritious.Depending on context, a particular noun could be modified by either a restrictive or non-restrictive adjective clause. For example, while"broccoli" is modified non-restrictively in the preceding sentence, it is modified restrictively in the following.*.The broccoliwhich (orthat) people leave uneatenis often nutritious.Adverbial clauseMain article:Adverbial clause"He saw Marywhen he was in New York" and "They studied hardbecause they had a test" both contain adverbial clauses (in italics).Adverbial clauses express when, why, where, opposition, and conditions, As with all dependent clauses, they cannot stand alone. For example,When he was in New Yorkis not a complete sentence; it needs to be completed by an independent clause. For example:*.He went to the Guggenheim Museumwhen he was in New York.or equivalently*.When he was in New York, he went to the Guggenheim Museum.Dependent clauses and sentence structureA sentence with anindependent clauseand one or more dependent clauses is referred to as acomplex sentence. One with two or more independent clauses and one or more dependent clauses is referredto as acompound-complex sentence. Here are some English examples:My sister criedbecause she scrapedher knee. (complex sentence)*.Subjects: My sister, she*.Predicates: cried, scraped her knee*.Subordinating conjunction: becauseWhen they told me(that) I won the contest, I cried, but I didn't faint.**(compound-complex sentence)*.Subjects: they, I, I, I*.Predicates: told me, won the contest, cried, didn't faint*.Subordinating conjunctions: when, that (explicit or understood)*.Coordinating conjunction: butThe above sentence contains two dependent clauses. "When they toldme" is one; the other is "(that) I won the contest", which serves as the object of the verb "told." The connecting word "that," if not explicitly included, is understood toimplicitly precede "I won" and in either case functions as a subordinating conjunction. This sentence also includes two independent clauses, "I cried" and"I didn't faint," connected by the coordinating conjunction "but." Thefirst dependent clause, together with its object (the second dependent clause), adverbially modifies the verbs of both main clauses.Non-finite dependent clausesMain articles:Non-finite clauseandBalancing and derankingDependent clauses may beheadedby aninfinitiveor othernon-finite verbform, which in linguistics is calledderanked. In these cases, thesubject of the dependent clause may take a non-nominativeform. An example is:*.I wanthim to vanish.See also*.Clause*.Independent clause*.Relative clause*.Conditional clause*.Relative pronoun*.Grammatical conjunction*.Sentence*.Compound sentence*.Simple sentence*.Subjunctive moodReferences*.Rozakis, Laurie (2003).The Complete Idiot's Guide to Grammar and Style pp. 153–159. Alpha.ISBN1-59257-115-8.External links*.Owl Online Writing Lab:Independent and Dependent Clauses*.Complex Sentences: Subordinate Clauses as Adverb Clauses