PowerPoint Presentation

To learn more about clauses, check out our slideshow, Clauses: Building Blocks for Sentences.



A clause is a group of related words containing a subject and a verb, such as “my hockey team won the tournament” (independent clause) or “because my hockey team won the tournament” (dependent clause). A clause can be usefully distinguished from a phrase, which is a group of related words that does not contain a subject-verb relationship, such as “in the morning” or “running down the street.” A review of the different kinds of phrases might be useful to get a better understanding of the difference between clauses and phrases.


Words We Use to Talk about Clauses

To understand how clauses work, it is important to learn the various terms used to define and classify clauses. Clauses can be categorized into independent and dependent clauses. This simply means that some clauses can stand by themselves, as separate sentences, and some can’t. Another term for dependent clause is subordinate clause: this means that the clause is subordinate to another element (the independent clause) and depends on that other element for its meaning. The subordinate clause is created by a subordinating conjunction or another dependent word.

An independent clause, “She is older than her brother” (which could be its own sentence), can be turned into a dependent or subordinate clause when the same group of words begins with a dependent word: “Because she is older than her brother, she tells him what to do.”

Clauses are also classified as restrictive and non-restrictive clauses. (The words “essential” or “defining” and “nonessential” or “non-defining” are sometimes used and mean the same thing as “restrictive” and “non-restrictive,” respectively.) A non-restrictive clause is not essential to the meaning of the sentence; it can be removed from the sentence without changing its basic meaning. A non-restrictive clauses is often set apart from the rest of the sentence by a comma (or a pair of commas if it’s in the middle of a sentence). For example:

  • Professor Villa, who teaches at the Office Administration program, can type 132 words a minute.

Relative clauses are dependent clauses introduced by a relative pronoun (that, which, whichever, who, whoever, whom, whomever, whose, and of which). Relative clauses can be either restrictive or non-restrictive. Review the section on comma usage for additional help in determining whether relative clauses are restrictive or non-restrictive and whether commas should be used to set them off from the rest of the sentence. In a relative clause, the relative pronoun is the subject of the verb (remember that all clauses contain a subject-verb relationship) and refers to (relates to) something preceding the clause. For example:

  • Giuseppe said that the plantar wart, which had been bothering him for years, had to be removed.

In this sentence, the clause in italics is a restrictive [essential] clause [a noun clause — see below] and will not be set off by a comma; the underlined relative clause [modifying “wart”] is non-restrictive [nonessential — it can be removed from the sentence without changing the meaning of the sentence] and is set off by commas.

Some relative clauses will refer to more than a single word in the preceding text; they can modify an entire clause or even a series of clauses.

  • Charlie didn’t get the job in administration, which really surprised his friends.
  • Charlie didn’t get the job in administration, and he didn’t even apply for the Dean’s position, which really surprised his friends.

A relative clause that refers to or modifies entire clauses in this manner is called a sentential clause.


Independent Clauses

Independent clauses could stand by themselves as discrete sentences. When they do stand by themselves, separated from other clauses, they’re normally referred to simply as sentences, not clauses. The ability to recognize a clause and to know when a clause is capable of acting as an independent unit is essential to correct writing and is especially helpful in avoiding sentence fragments and run-on sentences. It is also important to learn how to combine independent clauses into larger units of thought. For example:

  • Bob didn’t mean to do it, but he did it anyway.

Here, we have two independent clauses — Bob didn’t mean to do it and he did it anyway — connected by a comma and a coordinating conjunction (but). If the word but is missing from this sentence, the sentence would contain a comma splice: two independent clauses would be incorrectly connected with only a comma between them.


Punctuation Between Two Independent Clauses

Independent clauses can be connected (or separated, depending on your point of view) in a variety of ways. When two ideas come together and either one of them can stand by itself — as its own, independent sentence — the following kinds of punctuation are possible.

Period + start a new sentence

My grandmother refuses to go to bed early. She thinks she’s going to miss out on some of the action.

Comma + a coordinating conjunction

My grandmother refuses to go to bed early, and I’m afraid she will catch a bad cold.
Note: It may help you remember these conjunctions by recalling that they all have fewer than four letters. Also, remember the acronym FANBOYS:For-And-Nor-But-Or-Yet-So.

Semicolon by itself

In spite of her cold, my grandmother refuses to go to bed early; she is afraid she will miss something.

Semicolon + a conjunctive adverb followed by comma

My grandmother has stayed up late four nights in a row; as a result, she cannot seem to get well.Note: Semicolons should be used sparingly and only when the two independent clauses involved are closely related and nicely balanced in terms of length and import.

There are other ways to combine independent clauses – by turning them into various kinds of modifying phrases. Review the section on transitions between ideas.


Dependent Clauses

Subordination involves turning one of the clauses into a subordinate element through the use of a subordinating conjunction (sometimes called a dependent word) or a relative pronoun. When the clause begins with a subordinating word, it is no longer an independent clause; it is called a dependent or subordinate clause because it depends on something else (the independent clause) for its meaning.

For example:

  • Although Ramonita often thought about joining the choir, she never talked to her friends about it.
  • Ramonita never talked to her friends about joining the choir, because she was afraid they would make fun of her.
  • Yasmin is Ramonita’s sister. Yasmin told Ramonita to join the choir no matter what her friends said.

Joining these with the use of a relative clause:

  • Yasmin, [who is] Ramonita’s sister, told Ramonita to join the choir no matter what her friends said.

Although dependent clauses always contain a subject and a verb, they cannot stand by themselves and make good sense. They must be combined with an independent clause so that they become part of a sentence that can stand by itself. Dependent clauses perform various functions within a sentence. There are three basic kinds of dependent clauses, categorized according to their function in the sentence: noun clauses, adjective clauses and adverb clauses. Noun clauses can do anything that nouns can do. Adjective clauses work like multi-word adjectives. Adverb clauses provide information about what is going on in the main (independent) clause: where, when, or why.

Noun Clause as Subject

  • What they did with the treasure remains a mystery.
  • Whatever you want for dessert is fine with me.
  • That you should feel this way about her came as a great surprise to us.

Noun Clause as Object

  • Juan finally revealed what he had done with the money.
  • Her husband spent whatever she has saved over the years.
  • I don’t know what I should do next.

Noun Clause as Object of Preposition

  • In fact, he wrote a book about what he had done over the years.
  • We are interested in what he does for a living.

Noun Clause as Predicate Nominative

  • The trouble was that they had never been there before.
  • The biggest disappointment of last season was that the women’s team didn’t make it to the final four.

Adjective Clause

  • My brother, who now teaches math in a small college, never liked math in high school.
  • The dealership that sold more cars ended up actually losing money.
  • The Federated Bank, which was founded nearly two centuries ago, folded during the state’s economic crisis.

Adverb Clause

  • The team had fallen behind by ten points before they were able to figure out the opponent’s defense.
  • Since he started working nights, he doesn’t see much of his kids.
  • While Josie sat inside watching television, Gladys shoveled the driveway.


Combinations of Clauses

Review the section on comma usage for advice on the punctuation requirements when dependent and independent clauses are combined. Review the section on sentence constructions for help in understanding the variety of sentence patterns. Pay special attention to various sentence types: simple, compound, complex, and compound-complex sentences. These are defined by their essential ingredients: the clauses that make them up. There is also a quiz at the end of that section that will test your ability to distinguish among the kinds of clauses that make up a sentence.


Elliptical Clauses

Elliptical clauses are grammatically incomplete in the sense that they are missing either the relative pronoun (dependent word) that normally introduces such a clause or something from the predicate in the second part of a comparison. The missing parts of the elliptical clause can be guessed from the context and most readers are not aware that anything is missing. In fact, elliptical clauses are regarded as both useful and correct because they are often elegant, efficient means of expression. (The omitted words are noted in brackets below).

  • Coach Espinoza knew [that] this team would be the best [that] she had coached in recent years.
  • Though [they were] sometimes nervous on the court, her recruits proved to be hard workers.