What are the big six sentence structures?

There isn't a universally accepted list of "big six" sentence structures. However, there are six common and fundamental sentence structures that are often taught in grammar classes. These structures are based on the arrangement of subject, verb, and object within a sentence. Here they are:

1. Simple Sentence: This is the most basic sentence structure, containing a subject and a verb.

* Example: The cat sleeps. (Subject: cat, Verb: sleeps)

2. Compound Sentence: This structure combines two or more simple sentences using a coordinating conjunction (for, and, nor, but, or, yet, so).

* Example: The cat sleeps, and the dog barks.

3. Complex Sentence: This structure combines a dependent clause (a clause that cannot stand alone) and an independent clause (a clause that can stand alone) using a subordinating conjunction (because, although, since, while, etc.).

* Example: The cat sleeps because it's tired. (Dependent clause: "because it's tired", Independent clause: "The cat sleeps")

4. Compound-Complex Sentence: This structure combines a compound sentence and a complex sentence.

* Example: The cat sleeps because it's tired, and the dog barks because it's hungry. (Compound: "The cat sleeps, and the dog barks", Complex: "because it's tired", "because it's hungry")

5. Declarative Sentence: This is a statement that makes a declaration.

* Example: The cat is sleeping.

6. Interrogative Sentence: This is a question.

* Example: Is the cat sleeping?

It's important to remember that there are many variations within these six basic structures. You can add modifiers, phrases, and other elements to create more complex and nuanced sentences.