Understanding the Four Sentence Types
| Learning Objectives: - Identify and create simple sentences.
- Identify and create compound sentences.
- Identify and create complex sentences.
- Identify and create compound-complex sentences.
|
LESSON
SentencesA group of words, phrases, or clauses that expresses a complete thought. A complete sentence has these characteristics: a capitalized first word, a subject and a predicate, and end punctuation, such as a period (.), question mark (?), or exclamation mark (!). fall into one of four categories: simple, compound, complex, and compound-complex. The type of sentence that is most appropriate depends on the writer's purposeThe reason the writer is writing about a topic. It is what the writer wants the reader to know, feel, or do after reading the work. or focus. Good writing generally uses a variety of all four sentences to provide more detail and prevent readers from growing tired of one sentence pattern.
Simple Sentences
A simple sentenceOne of the four sentence types that contains a subject and a predicate. Example: The girl went for a walk. The subject is the girl. The predicate is went for a walk. consists of a subjectIn grammar, a part of speech that refers to the “doer” in the sentence (who or what). A subject is usually a person, place or thing. and a predicatePart of a sentence or a clause that has a verb and any modifiers or objects. Example: The girl went for a walk. The subject is the girl. The predicate is went for a walk.. It is also called an independent clausePart of a sentence that contains a subject and a predicate and can stand on its own as a complete sentence. Example independent clause: The boy ate the freshly picked apple with delight. The subject is the boy, the predicate is the verb ate, plus the modifiers the freshly picked apple with delight.. To qualify as a sentence, it must express a complete thought. If it does not, it is a sentence fragmentA grammatical error that occurs when a sentence is missing either a subject or a predicate, making it incomplete..
Simple sentence examples:
- The student asked his teacher a question.
- Who asked a question?
- The student didn't know how to dissect a frog.
Compound Sentences
Compound sentencesOne of the four sentence types that is composed of two or more independent clauses joined together using proper punctuation. are two or more independent clauses, also known as simple sentences, correctly joined by using one of three methods. First, you can join them with a comma(,) A punctuation mark used to group and separate information in sentences. and coordinating conjunctionPart of speech that connects words, phrases, and independent clauses. The acronym FANBOYS—for, and, nor, but, or, yet, so—can help you remember coordinating conjunctions., also known by the acronym FANBOYS (for, and, nor, but, or, yet, so).
Compound sentence examples:
- The student didn't know how to dissect a frog, but his lab partner taught him everything.
- The student didn't know how to dissect a frog, so his lab partner taught him everything.
Another way to create a compound sentence is to join the two independent clauses with a semicolon(;) A punctuation mark used to connect major parts of sentences of equal grammatical rank. For example, semicolons are used to connect two independent clauses into one sentence.. You can use a semicolon wherever you might use a period, but without capitalizing the first letter in the second independent clause.
Example:
- The student didn't know how to dissect a frog; his lab partner taught him everything.
You can also make compound sentences by joining independent clauses together with a semicolon, conjunctive adverbA type of parenthetical expression; adverbs that join ideas together. Examples: also, first, however, next., and a comma. The words as a result, consequently, however, moreover, and therefore are all examples of conjunctive adverbs.
Example:
- The student didn't know how to dissect a frog; however, his lab partner taught him everything.
Complex Sentences
A complex sentenceOne of the four sentence types that is composed of an independent clause and a dependent clause. consists of an independent clause and a dependent clausePart of a sentence that contains a subject and a verb but is unable to stand on its own because it is incomplete in some way. Example of a dependent clause: Because it was a freshly picked apple, the boy ate it with delight. In this sentence, Because it was a freshly picked apple is a dependent clause. It has a subject (it) and a verb (was), but it cannot stand on its own without the second part of the sentence. joined together. While a dependent clause has a nounA part of speech that refers to a person, place, or thing. Examples include: swimmer, lake, sunscreen. and a verbA part of speech that refers to what is happening, the action, what the subject is doing, or how it is “being.” Examples include: sleep, to be, think. like an independent clause, it does not express a complete thought. There are two types of dependent clauses: subordinating and relative.
A subordinating clauseA type of dependent clause that begins with a subordinating conjunction. Example: After the game. The subject: the game, is modified by the subordinating conjunction: After. begins with a subordinating conjunctionPart of speech that connects dependent clauses. A subordinating conjunction comes at the beginning of a dependent clause and shows the relationship between the clauses it connects. Examples of subordinating conjunctions include: after, if, while, unless. and then contains a subject and a predicate.
| Common Subordinating Conjunctions |
| after | even though | until |
| although | if | when |
| as | in order that | whenever |
| as if | just as | where |
| as long as | now that | whereas |
| as much as | provided that | wherever |
| as soon as | since | whether |
| as though | so that | which |
| because | than | while |
| before | that | who |
| even | though | whoever |
| even if | unless | why |
Complex sentence examples:
- Complex sentence with a subordinating clause: Since the student didn't know how to dissect a frog, his lab partner taught him everything.
- Complex sentence with a subordinating clause: The student's lab partner taught him how to dissect a frog because the student didn’t know anything about dissecting.
A relative clauseA type of dependent clause that begins with a relative pronoun. A relative clause modifies the words or phrases in the main clause. Example: This is the boy who always finishes his homework on time. The subject: the boy, is modified by the relative clause: who always finishes his homework on time. contains a relative pronounA word that replaces a noun that it relates to; it also introduces a relative clause. Examples: what, who, whom, whose, whoever, whomever, and which. and a predicate. Relative pronouns include that, what, which, who, whoever, whom, whomever, and whose.
Examples:
- Complex sentence with a relative clause: The student who didn't know how to dissect a frog learned everything from his lab partner.
- Complex sentence with a relative clause: His lab partner taught him everything that was important.
Compound-complex Sentences
In a compound-complex sentenceOne of the four sentence types in which one or both of the independent clauses has a subordinating clause, relative clause, or both., one or both of the independent clauses has a subordinating clause, relative clause, or both.
Compound-complex sentence examples:
- Compound sentence with a subordinating clause: Since the student didn't know how to dissect a frog, he thought he would fail his biology lab, but his lab partner taught him everything.
- Compound sentence with a relative clause: The student who didn't know how to dissect a frog began to worry that he would fail his biology lab, but his lab partner taught him everything.
- Compound sentence with both subordinating and relative clauses: The student who didn't know how to dissect a frog began to worry that he would fail his biology lab, but his lab partner taught him everything because she knew that her grade would be tied to his poor performance.
+ PRACTICAL APPLICATIONA simple sentence is like vanilla ice cream. It's perfectly good on its own, but a world with only vanilla ice cream would be very boring. Similarly, simple sentences are great, but using too many of them sounds choppy, and you are likely to lose the reader's attention. The other three sentence types provide interest and sophistication that you can bring to both academic and professional writing. If you properly use these four sentence types, you will avoid run-on sentencesA grammatical error that occurs when a sentence has two or more independent clauses joined together incorrectly., comma splicesType of run-on sentence that occurs when two independent clauses (two complete sentences) are joined with a comma instead of a period, semicolon, or comma with a conjunction., and fragments, which will strengthen your credibility.
Example 1: Look carefully at each of the following sentences and notice which type of sentence it is (simple, compound, complex, or compound-complex).
- A student must participate and take notes in most classes.
Simple
- A student who wants to do well in college should participate and take notes in most classes.
Complex (relative clause: who wants to do well in college)
- Most college students want to do well in their classes, so they participate and take notes in most classes.
Compound (coordinating conjunction: so)
- If students want to do well in college, they should participate and take notes in most classes.
Complex (subordinating clause: If students want to do well in college)
- Students who want to do well in college should participate and take notes in most classes, or they may earn an "F" in their courses.
Compound-complex (relative clause: who want to do well in college in the first independent clause; coordinating conjunction: or in the second clause)
Example 2: Now, read the sentence below and notice how two simple sentences are made from it:
- Computers are an important part of life today, and most people should learn to use them.
Simple sentences:
- Computers are an important part of life today.
- Most people should learn to use them.
Note the different ways these two simple sentences are combined to create each of the following sentence types.
Compound sentence:
- Computers are an important part of life today, so most people should learn to use them.
Complex sentence with a relative clause:
- Most people should learn to use the computers that are an important part of life today.
Complex sentence with a subordinating clause:
- Because computers are an important part of life today, most people should learn to use them.
Compound-complex sentence:
- Computers are an important part of the lives that we lead today, and most people should learn to use them.
Exercise 1: Look carefully at each of the following sentences and indicate which type of sentence it is (simple, compound, complex, or compound-complex).
- Although syllabi seem boring, students need to read them thoroughly.
Complex (subordinating clause: Although syllabi seem boring)
- Syllabi may seem boring; however, students still need to read them thoroughly.
Compound (semicolon and conjunctive adverb: however)
- Students need to read their syllabi thoroughly.
- Syllabi, which seem boring, are necessary to understand the requirements in any course, so students need to read them thoroughly.
Compound-complex (relative clause: which seem boring in the first independent clause and coordinating conjunction so in the second independent clause)
- Syllabi may seem boring, but students who want to do well need to read them thoroughly.
Compound-complex (coordinating conjunction: but and relative clause: who want to do well in the second independent clause)
Exercise 2: Now, read the following sentence and make two simple sentences from it.
Teachers must know their subject matter, and they should enjoy teaching.
- Create two simple sentences.
Teachers must know their subject matter. They should enjoy teaching.
Using the two simple sentences from above, combine them to create each of the following sentence types. Add information if necessary.
- Create a compound sentence.
Teachers must know their subject matter, and they should enjoy teaching.
- Create a complex sentence with a relative clause.
Teachers who are effective must know their subject matter and enjoy teaching.
- Create a complex sentence with a subordinating clause.
While teachers must know their subject matter, they should also enjoy teaching.
- Create a compound-complex sentence.
Teachers must know their subject matter, but those who are most effective also enjoy teaching.
Is there a sentence type that you typically use in your own writing? If so, which one and why?
I usually use compound sentences because it is an easy way to combine two complete thoughts.
How can knowing the four sentence types help you avoid run-ons, comma splices, and fragments?
Knowing how to use compound and complex sentences helps me show the relationship between clauses instead of simply writing thoughts as isolated ideas or running them together without showing a connection.
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