What is the meaning of complex sentences?

Complex sentences are sentences that contain one independent clause and at least one dependent (or subordinate) clause. The dependent clause cannot stand alone as a complete sentence, as it relies on the independent clause for its meaning. Complex sentences are used to convey more nuanced ideas, show relationships between different thoughts, or add detail to a statement. For example, "Although it was raining, we decided to go for a walk" features a dependent clause that adds context to the independent clause.