A compound-complex sentence is one that contains at least two independent clauses (that’s the compound-sentence part) and at least one dependent clause (that’s the complex-sentence part).
A periodic sentence (often called a suspended sentence) is one in which the sense of the sentence is not complete until the final words. Here’s an example from Dylan Thomas’s “ A Child’s Christmas in Wales”:
“Years and years ago, when I was a boy, when there were wolves in Wales, and birds the color of red-flannel petticoats whisked past the harp-shaped hills, when we sang and wallowed all night and day in caves that smelt like Sunday afternoons in damp front farmhouse parlors, and we chased, with the jawbones of deacons, the English and the bears, before the motor car, before the wheel, before the duchess-faced horse, when we rode the daft and happy hills bareback, it snowed and it snowed.”
As you can see, the meaning (sense) of the sentence isn’t complete or even clear until the words “it snowed and it snowed.” The snow is what the sentence is about.
Years ago I was writing a series of bear sentences for a possible children’s project, but, aside from the sentences, I wasn’t sure what the project could be. It was too short for a book. A series of cards? Posters? Placemats? I could never work this problem out, and so the project sits in my filing cabinet.
Except that, every once in a while, I revisit the compound-complex bear sentence just to laugh at the fact that the meaning isn’t clear until the very end.
Compound-Complex Sentence, Suspended
The bear who painted a large green pear won a purple ribbon from the judges, and the bear who painted a big blue square around the large green pear also won a purple ribbon, but the ribbons were quickly taken away after the second bear ate the first bear’s pear and the first bear squashed the second bear’s square and the judges.
Barbara Gregorich blogged about sentences in Sentences and Train Wrecks, but luckily no bears squashed her.