The examples of the sentences will be from the American classic short story "The Open Boat" by Stephen Crane.
A compound-complex sentence is defined as sentence which contains two or more independent clauses and one or more dependent clause(s). An independent clause is essentially a complete sentence because it makes sense by itself. On the other hand, a dependent clause is a group of words that contain a subject/predicate but only has meaning when connected to and independent clause.
In the compound sentence there will be two or more separate complete sentences connected in some way: (a) a comma and conjunction; (b) a semicolon and a conjunctive adverb followed by comma; or a semicolon by itself.
Here are examples to show each type of compound sentence and its connectors.
(a) It was a thin little oar, and it seemed often ready to snap.
(b) The oiler took both oars; then, the correspondent took both oars.
(c) It was not an amusement; it was a diabolical punishment.
Here is the compound-complex sentence:
As each salty wall of water approached, it shut all else from the view of the men in the boat, and it was not difficult to imagine that this was the final outburst of the ocean.
As each salty wall of water approached, = dependent clause
it shut all else from the view of the men in the boat, = independent clause
it was difficult to imagine that this was not the final outburst of the ocean = independent clause and dependent clause