Compound sentences contain two or more independent clauses (clauses that can stand on their own as a complete sentence) joined by a conjunction and express multiple ideas or thoughts. They are typically used to combine two or more ideas or thoughts in a single sentence.

Compound-complex sentences contain two or more independent clauses and one or more dependent clauses (clauses that cannot stand on their own as a complete sentence) and express multiple main ideas with additional information or detail. They are typically used to combine multiple main ideas and add detail or context to those ideas.

Here are some examples to illustrate the difference between compound and compound-complex sentences:

Compound sentences:

• “I am going to the store, but I need to pick up some milk first.”
• “The sun is shining today, and the weather is warm.”
• “I have a meeting at 10 AM, and I need to finish my presentation before then.”
• “I think pizza is the best food in the world, but my friend disagrees.”
• “The cat is sleeping on the couch, and the dog is lying on the floor.”

Compound-complex sentences:

• “I am going to the store to pick up some milk, but I also need to buy bread because we’re out of bread.”
• “The sun is shining today, and the weather is warm, but it was supposed to rain according to the forecast.”
• “I have a meeting at 10 AM, which means I need to finish my presentation before then, but I also need to print out copies for everyone attending.”
• “I think pizza is the best food in the world, even though some people might disagree because it has so many topping options.”
• “The cat is sleeping on the couch, and the dog is lying on the floor, but I have to be quiet because my roommate is sleeping in the bedroom.”