Clauses are defined as grammatical structures that contain a subject and a predicate. The English language has four forms of clauses:
Each grammatical form of clause in English performs distinct grammatical functions.
Verb clauses are defined as independent clauses formed by a subject and a predicate. For example, the following italicized clauses are examples of verb clauses:
- The puppy is barking.
- Did you take out the garbage?
- Wash your hands!
Verb clauses perform verbal functions. Verbal functions correspond to the forms of sentences in English: declarative sentences, interrogative sentences, and imperative sentences. The three verbal functions in English grammar are:
- Declaration or statement (declarative sentence)
- Question (interrogative sentence)
- Command (imperative sentence)
All sentences contain at least one verb clause. Verb clauses are also referred to as main clauses.
Noun clauses are defined as subordinate clauses formed by a subordinating conjunction followed by a clause. The subordinating conjunctions in English that introduce noun clauses are that, Ø, if, whether, wh- words, and wh-ever words. For example, the following italicized clauses are examples of noun clauses:
- The library will send a bill to whoever damaged this book.
- Whether you will pay for the damage is not even a question.
- The judge has given that you behaved well after your arrest some consideration.
Noun clauses perform nominal functions, or functions prototypically performed by noun phrases. The nine main functions of noun clauses in English grammar are:
- Subject complement
- Direct object
- Object complement
- Indirect object
- Prepositional complement
- Adjective phrase complement
- Noun phrase complement
Noun clauses are also referred to as content clauses.
Adjective clauses are defined as subordinate clauses formed by a subordinating conjunction followed by a clause. The subordinating conjunctions in English that introduce adjective clauses are who, whom, that, Ø, which, whose, when, and where. For example, the following italicized clauses are examples of adjective clauses:
- The woman that works in the bakery is my neighbor.
- The car you hit belongs to the man whose daughter is my classmate.
- The restaurant where you left you purse is known for its unique pasta dishes.
The primary grammatical function of adjective clauses is noun phrase modifier. Noun phrase modifiers are defined as words, phrases, and clauses that describe or modify a noun phrase. Adjectives clauses may also, although rarely, function as verb phrase modifiers, prepositional phrase modifiers, and noun clause modifiers.
Adjective clauses are also referred to as relative clauses. The subordinating conjunctions that introduce adjective clauses are also called relative pronouns.
Adverb clauses are defined as subordinate clauses formed by a subordinating conjunction followed by a clause. Some of the more common subordinating conjunctions in English that introduce adverb clauses include:
- even though
- so that
For example, the following italicized clauses are examples of adverb clauses:
- After she gave the baby a bath, she decided to take a nap.
- The girl cannot usually eat beef stew because she is allergic to carrots.
- The couple has been saving money so that they can go on a vacation.
All adverb clauses perform the grammatical function of adjunct adverbial. Adjunct adverbials are words, phrases, and clauses that modify or describe an entire clause by providing additional information about time, place, manner, condition, purpose, reason, result, and concession.
The four forms of clauses in English are verb clause, noun clause, adjective clause, and adverb clause. Verb clauses perform three grammatical functions: declaration, question, and command. Noun clauses perform nine functions: subject, subject complement, direct object, object complement, indirect object, prepositional complement, adjective phrase complement, noun phrase complement, and appositive. Adjective clauses primarily perform the single function of noun phrase modifier but can also function as verb phrase modifiers, prepositional phrase modifiers, and noun clause modifiers. Adverbs perform the single function of adverbial.
Hopper, Paul J. 1999. A short course in grammar. New York: W. W. Norton & Company.
Huddleston, Rodney. 1984. Introduction to the grammar of English. Cambridge: Cambridge University Press.