Compound-complex sentences are sentences that combine two or more independent clauses and at least one dependent clause. They offer a way to express complex relationships and incorporate multiple ideas within a single sentence.

Key points about compound-complex sentences include:

1. Independent clauses: A compound-complex sentence consists of independent clauses that can stand alone as complete sentences. These clauses express main ideas or complete thoughts.

   – Example: “She went to the party, and he stayed at home, but they both had a great time.”

   – Example: “I studied for the test, but I still failed because I didn’t understand the material.”

2. Dependent clauses: Compound-complex sentences also include dependent clauses, which cannot stand alone as complete sentences. These clauses provide additional information or support for the main ideas expressed in the independent clauses.

   – Example: “Although she was tired, she stayed up late to finish her project.”

   – Example: “He went to the store because he needed to buy some groceries.”

3. Conjunctions: Independent clauses in a compound-complex sentence are joined by coordinating conjunctions like “and,” “but,” “or,” “nor,” “for,” “yet,” and “so.” Dependent clauses are introduced by subordinating conjunctions.

   – Example: “She went to the party, and he stayed at home, but they both had a great time.”

   – Example: “Although she was tired, she stayed up late to finish her project.”

4. Punctuation: In compound-complex sentences, a comma is typically used before the coordinating conjunction when joining two independent clauses. Dependent clauses at the beginning or middle of the sentence are usually set off by commas.

   – Example: “She went to the party, and he stayed at home, but they both had a great time.”

   – Example: “Although she was tired, she stayed up late to finish her project.”

By constructing compound-complex sentences effectively, writers can convey complex relationships, provide additional information, and express multiple ideas within a structured framework. Understanding how to use compound-complex sentences enhances the clarity, coherence, and sophistication of communication.