Here's how we can break down sentence complexity:
* Simple Sentence: One independent clause (subject + verb)
* Compound Sentence: Two or more independent clauses joined by a coordinating conjunction (for, and, nor, but, or, yet, so)
* Complex Sentence: One independent clause and one or more dependent clauses (clauses that cannot stand alone)
What you're likely thinking about is a sentence with multiple independent clauses and multiple dependent clauses.
Here's an example:
* "Because the rain was pouring, the children couldn't go outside, but their mother read them a story, which they enjoyed very much."
This sentence has two independent clauses:
* The children couldn't go outside.
* Their mother read them a story.
And it has two dependent clauses:
* Because the rain was pouring.
* Which they enjoyed very much.
While there isn't a specific term for this type of sentence, it's a complex and well-structured example of effective writing.
Let me know if you have more questions about sentence structure!