Compound Sentence

In this article, we provide a comprehensive guide to compound sentences. We begin with a clear definition, followed by an exploration of the different types of compound sentences. You'll learn how to identify a compound sentence and understand its structure. We also cover coordinating conjunctions, their meanings, and the punctuation rules associated with compound sentences. Additionally, we highlight the differences between simple, compound, and complex sentences and address common errors found in compound sentence construction, helping you master this important aspect of grammar.

Table of Contents

Definition of Compound Sentence

A compound sentence is a sentence that consists of two or more independent clauses joined by a coordinating conjunction (such as and, but, or, nor, for, so, yet) or a semicolon (;). Each independent clause has its own subject and verb and can stand alone as a complete sentence.

A compound sentence is a sentence that contains at least two independent clauses joined by a coordinating conjunction or a semicolon to express related ideas.

Types of Compound Sentence

A compound sentence consists of two or more independent clauses joined by a coordinating conjunction, a semicolon, or a transitional expression. There are three main types of compound sentences:

Compound Sentences with Coordinating Conjunctions

Coordinating conjunctions: for, and, nor, but, or, yet, so (FANBOYS)

Example:

  • I wanted to go for a walk, but it started raining.
    (Two independent clauses joined by 'but')

Compound Sentences with a Semicolon

- A semicolon (;) is used instead of a conjunction.

Example:

  • She loves to read; her brother prefers watching movies.
    (Two independent clauses joined by a semicolon)

Compound Sentences with a Conjunctive Adverb or Transitional Expression

Conjunctive adverbs: however, therefore, moreover, consequently, otherwise, furthermore, nevertheless, etc.

A semicolon is used before the conjunctive adverb, and a comma follows it.

Example:

  • He studied hard; therefore, he passed the exam.
    (Two independent clauses joined by 'therefore')

Identifying a Compound Sentence

A compound sentence is a sentence that contains two or more independent clauses joined by a coordinating conjunction, a semicolon, or a transitional expression.

How to Identify a Compound Sentence:

Look for Two Independent Clauses: An independent clause has a subject and a verb and expresses a complete thought.

  • She likes coffee (independent clause) + He prefers tea (independent clause).

Check for Coordinating Conjunctions (FANBOYS): The clauses are often connected by 'FANBOYS':

  • For
  • And
  • Nor
  • But
  • Or
  • Yet
  • So
  • Example: She likes coffee, but he prefers tea.

Check for a Semicolon (;): If two independent clauses are joined by a semicolon, it's a compound sentence.

  • She likes coffee; he prefers tea.

Check for a Conjunctive Adverb: Words like 'however, therefore, moreover, consequently, otherwise' can connect two independent clauses with a semicolon and a comma.

  • She likes coffee; however, he prefers tea.

Examples of Compound Sentences:

  • I wanted to go for a walk, but it started raining.
  • She studied hard; therefore, she passed the exam.
  • You can have cake, or you can have ice cream.

Structure of a Compound Sentence

A compound sentence consists of two or more 'independent clauses' joined by a 'coordinating conjunction', a 'semicolon', or a 'conjunctive adverb'. Each independent clause in a compound sentence can stand alone as a complete sentence.

Structure of a Compound Sentence

  • Independent Clause + Coordinating Conjunction + Independent Clause
  • Independent Clause + Semicolon (;) + Independent Clause
  • Independent Clause + Semicolon (;) + Conjunctive Adverb + Comma (,) + Independent Clause

Examples:

Using a Coordinating Conjunction (FANBOYS)

  • I wanted to go outside, but it was raining.
  • She studied hard, so she passed the exam.

    (FANBOYS: For, And, Nor, But, Or, Yet, So)

Using a Semicolon (;)

  • I wanted to go outside; it was raining.
  • She studied hard; she passed the exam.

Using a Conjunctive Adverb

  • I wanted to go outside; however, it was raining.
  • She studied hard; therefore, she passed the exam.

Coordinating Conjunctions and Their Meanings

Coordinating conjunctions are words that connect two independent clauses to form a compound sentence. They help to show the relationship between the ideas in the clauses. The most common coordinating conjunctions can be remembered using the acronym 'FANBOYS':

  • For – Explains reason or purpose.
  • And – Adds one idea to another.
  • Nor – Presents a negative alternative.
  • But – Shows contrast between ideas.
  • Or – Presents a choice or alternative.
  • Yet – Shows contrast, similar to 'but' but often with an unexpected twist.
  • So – Shows result or consequence.

Examples of Compound Sentences Using Coordinating Conjunctions:

  • For – He didn’t go to work, for he was feeling sick.
    (Shows reason: because he was sick.)
  • And – She enjoys painting, and she loves playing the piano.
    (Adds another idea.)
  • Nor – He doesn’t like coffee, nor does he drink tea.
    (Shows a negative alternative.)
  • But – I wanted to stay longer, but I had to leave early.
    (Shows contrast.)
  • Or – You can have cake, or you can choose ice cream.
    (Presents a choice.)
  • Yet – She was tired, yet she continued to work.
    (Shows an unexpected contrast.)
  • So – It started raining, so we took shelter.
    (Shows cause and effect.)

Punctuation Rules

A compound sentence consists of two or more independent clauses joined by a coordinating conjunction, a semicolon, or a transitional expression. Here are the key punctuation rules:

Use a Comma Before a Coordinating Conjunction: When two independent clauses are joined by a 'coordinating conjunction' (FANBOYS: For, And, Nor, But, Or, Yet, So), use a 'comma' before the conjunction.

Example:

  • I wanted to go for a walk, but it started raining.
  • She studied all night, so she passed the test.

Use a Semicolon to Join Two Independent Clauses: If two independent clauses are closely related and not joined by a coordinating conjunction, use a 'semicolon' instead of a comma.

Example:

  • I love reading novels; my sister prefers poetry.
  • We planned a trip; however, the weather was bad.

Use a Semicolon Before a Transitional Expression: If a transitional expression (however, therefore, consequently, nevertheless) connects two independent clauses, use a 'semicolon before' it and a 'comma after' it.

Example:

  • She wanted to attend the party; however, she had a prior commitment.
  • He was running late; therefore, he took a taxi.

Avoid Run-on Sentences and Comma Splices: A run-on sentence occurs when independent clauses are joined without proper punctuation. A comma splice occurs when independent clauses are joined by only a comma without a conjunction.

Example:

  • I was tired, so I went to bed early.
  • I was tired; I went to bed early.

Difference Between Simple, Compound, and Complex Sentences

1. Simple Sentence: Simple Sentence Contains only one independent clause (a subject and a predicate). Expresses a complete thought.

  • She likes to read.

2. Compound Sentence: Contains two or more independent clauses (each with a subject and a predicate) joined by a coordinating conjunction (for, and, nor, but, or, yet, so). Each clause could stand alone as a simple sentence.

  • She likes to read, and he enjoys writing.

3. Complex Sentence: Contains one independent clause and at least one dependent clause (a group of words that cannot stand alone as a complete thought). Dependent clauses are connected to the independent clause by subordinating conjunctions (because, although, since, if, when, etc.).

  • She likes to read because it helps her relax.

Common Errors in Compound Sentences

Here are some common errors in compound sentences:

Comma Splice: This occurs when two independent clauses (complete sentences) are joined together with just a comma, without a coordinating conjunction or proper punctuation.

  • ✘ I went to the store, I bought some milk.
  • ✓ I went to the store, and I bought some milk.

Run-on Sentences: A run-on sentence happens when two independent clauses are joined without any punctuation or conjunction.

  • ✘ I wanted to go for a walk it was raining outside.
  • ✓ I wanted to go for a walk, but it was raining outside.

Misuse of Coordinating Conjunctions: Using the wrong coordinating conjunction (for, and, nor, but, or, yet, so) or leaving it out completely.

  • ✘ I wanted to go swimming but I forgot my towel.
  • ✓ I wanted to go swimming, but I forgot my towel.

Lack of Parallel Structure: When the items in a compound sentence are not balanced in structure.

  • ✘ She enjoys reading, playing tennis, and to swim.
  • ✓ She enjoys reading, playing tennis, and swimming.

Incorrect Punctuation: Sometimes compound sentences are improperly punctuated, particularly when not using a comma before the coordinating conjunction, if needed.

  • ✘ I like coffee but I prefer tea.
  • ✓ I like coffee, but I prefer tea.

Fragmenting the Sentence: Breaking up the sentence incorrectly where it no longer expresses a complete thought.

  • ✘ I went to the store. Because I needed milk.
  • ✓ I went to the store because I needed milk.