1. Understanding Compound Sentences

A compound sentence consists of two or more independent clauses joined by a coordinating conjunction (for, and, nor, but, or, yet, so) or a semicolon.

Example:

• “I wanted to go for a walk, but it started to rain.”

Comma Rule:

• Use a comma before the coordinating conjunction when connecting two independent clauses.

Examples:

• “She enjoys reading, and he enjoys writing.”
• “The sun was shining, so we went to the beach.”

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2. Understanding Complex Sentences

A complex sentence contains one independent clause and at least one dependent (or subordinate) clause. Dependent clauses begin with subordinating conjunctions such as because, although, since, if, when, while, and after.

Example:

• “Although it was raining, we decided to go for a hike.“

Comma Rules:

1. When the dependent clause comes first: Use a comma to separate it from the independent clause.

• Example: “Because it was late, we hurried home.”

1. When the independent clause comes first: Do not use a comma.

• Example: “We hurried home because it was late.“

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3. Combining Compound and Complex Sentences

Sentences can also be both compound and complex, containing multiple independent clauses and at least one dependent clause.

Example:

• “Although it was late, we decided to finish the project, and we submitted it on time.”

Comma Rule:

• Use commas to separate the clauses as per the rules for compound and complex sentences.

Example Breakdown:

• “Although it was late,” (dependent clause, followed by a comma)
• “we decided to finish the project” (independent clause)
• “and” (coordinating conjunction)
• “we submitted it on time” (second independent clause)

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4. Common Mistakes

• Omitting Commas in Compound Sentences: Failing to place a comma before the coordinating conjunction.
• Incorrect: “She wanted to play soccer but it started to rain.”
• Correct: “She wanted to play soccer, but it started to rain.”
• Using a Comma Before a Dependent Clause: Not placing a comma when the dependent clause follows the independent clause.
• Incorrect: “We went to the store because we needed groceries.”
• Correct: “Because we needed groceries, we went to the store.“