Final answer:
A complex sentence is a sentence that includes an independent clause and at least one dependent clause.
Step-by-step explanation:
A complex sentence is a sentence that includes an independent clause and at least one dependent clause. An example of a complex sentence is: 'Although it rained, the picnic went on as planned.' In this sentence, 'Although it rained' is the dependent clause, and 'the picnic went on as planned' is the independent clause.
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