Sentence structure refers to the structure of sentences in a language. Four types of sentence structures exist in the English language: simple sentences, compound sentences, complex sentences, and compound-complex sentences.
The first type of sentence in the English language is the simple sentence. A simple sentence consists of one verb clause. Verb clauses are independent clauses that consist of a subject and a predicate. Some grammars refer to verb clauses as main clauses, matrix clauses, or superordinate clauses.
- Subject | Predicate
- She | laughed.
- The fire alarm | sounded loudly.
- A strange girl | visits the library with her father.
- Forty-two thousand muskrats and one lone ox | have plotted to destroy the city.
The second type of sentence in the English language is the compound sentence. A compound sentence consists of two or more verb clauses joined by (1) a coordinating conjunction or (2) a correlative-coordinating conjunction pair. For example, the following sentences are compound sentences:
- Verb Clause | Coordinating Conjunction | Verb Clause
- She loved the ocean, | yet | she had never traveled to the sea.
- The boys picked burgers, | and | the girls chose chicken sandwiches.
- He hoped to buy a new car, | so | he saved up all of his money.
- The teacher allowed notes during the test, | but | all of the students failed anyway.
- Correlative Conjunction | Verb Clause | Coordinating Conjunction | Verb Clause
- Both | the stream flooded the bridge, | and | a fallen stream blocked the road.
- Either | he stops his rude behavior, | or | I leave the dinner early.
- Either | the news station is experiencing technical difficulties, | or | some really weird events are happening.
- Neither | the package arrived on time, | nor | the company received the shipping invoice.
The third type of sentence in the English language is the complex sentence. A complex sentence consists of one verb clause and one or more adverb clauses. Adverb clauses are dependent, or subordinate, clauses that consist of a subordinating conjunction followed by a clause and that perform adverbial functions. For example, the following sentences are complex sentences:
- Adverb Clause | Verb Clause
- After I made a mad dash to my car, | the rain started to let up.
- If he is early to the party, | the hostess will dash on the table in a lampshade.
- Verb Clause | Adverb Clause
- She failed her first semester of classes | because she partied too much and studied too little.
- The woman wore a football jersey | even though she disliked the sport.
- Adverb Clause | Verb Clause | Adverb Clause
- Although she felt badly, | the little girl refused to apologize | because she had a crush on the little boy.
- While his father worked on the truck, | the young man took careful notes | lest he miss an important step in the process.
The fourth type of sentence in the English language is the compound-complex sentence. A compound-complex sentence consist of two or more verb clauses and one or more adverb clauses. In other words, compound-complex sentences are combinations of one or more compound sentences and one or more complex sentences. For example, the following sentences are compound-complex sentences:
- Verb Clause | Adverb Clause | Conjunction | Verb Clause
- She had worked at the library | since she graduated, | but | she hoped to find a new job.
- Adverb Clause | Verb Clause | Conjunction | Verb Clause
- Although he loved the changing leaves, | he had never travelled to New England in the fall, | so | he decided to book a trip for next September.
- Verb Clause | Adverb Clause | Conjunction | Verb Clause | Adverb Clause
- Dad mowed the lawn | even though he is allergic to grass, | and | Mom baked some banana bread | even though she despises the smell of bananas.
Noun Clauses and Adjective Clauses
Different grammars analyze sentences containing noun clauses and adjective, or relative, clauses differently. One definition of the complex sentence is a sentence that contains a verb clause and a dependent, or subordinate clause. In addition to adverb clauses, noun clauses and adjective clauses are both dependent clauses. According to this definition, the following sentences are analyzed as complex sentences:
- That she failed her art class seriously surprised me. (noun clause)
- His parents gave that he wanted a computer for his birthday some thought. (noun clause)
- The woman to whom you delivered the flowers makes the final hiring decisions. (adjective clause)
- Reading, which is one of my favorite pastimes, keeps the mind stimulated. (adjective clause)
According to my definition of the complex sentence — a sentence that consists of one verb clause and one or more adverb clauses — sentences that consist of a single verb clause that contains noun clauses or adjective clauses (or both) are simple sentences. For example, I analyze the previous sentences as simple sentences.
Unlike adverb clauses, many noun and adjective clauses cannot be removed from the sentence without changing the grammar of the verb clause. For example, in the first sentence — That she failed her art class seriously surprised me — the noun clause That she failed her art class functions as the subject of the verb clause. Without the noun clause, the verb clause lacks a subject. The noun and adjective clauses are therefore constituents of the verb clause. Adverb clauses, however, are never constituents of the verb clause and can be removed without changing the grammar of the verb clause.
The constituency of noun and adjective clauses versus adverb clauses thus determines my definition of the complex sentence as a sentence that consists of one verb clause and one or more adverb clauses. A sentence that consists of a single verb clause, with or without noun or adjective clauses, is a simple sentence regardless of any noun or adjective clauses embedded in the grammatical structure of the verb clause.
The four types of sentence structures in the English language are simple sentences, compound sentences, complex sentences, and compound-complex sentences.
Brinton, Laurel J. & Donna M. Brinton. 2010. The linguistic structure of Modern English, 2nd edn. Amsterdam: John Benjamins Publishing Company.
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.