Understanding Compound-Complex Sentences

A compound-complex sentence is a sentence that contains two or more independent clauses (i.e., clauses that could stand alone as separate sentences) and one or more dependent clauses (i.e., clauses that cannot stand alone as separate sentences). The dependent clauses are often introduced by subordinating conjunctions such as because, although, if, unless, etc.

For example:

I went to the store because I needed milk, but when I got there, they were out of my favorite brand, so I had to choose a different one.

In this sentence, "I went to the store" and "I had to choose a different one" are independent clauses, while "because I needed milk" and "when I got there, they were out of my favorite brand" are dependent clauses. The dependent clauses cannot stand alone as separate sentences, but they provide additional information about the reason for going to the store and the outcome of the trip.