Sentences are where the hard work of writing begins, but also where a lot of the joy in that work happens. I think it's a shame that sentences don't get more attention and love. Not only because, 20 years into making my living as a writer, I'm neccessarily a sentence obsessive, but because understanding sentences unlocks many of the mysteries of writing. Among them the diffuse artefact of writing craft we call "voice".
Here are my condensed revision notes. A sentence begins will a kernel or base clause, usually composed of a subject and a predicate. The base clause and any information added to it express a set of propositions. Sentences grow from a propositional base in three ways; connective, adjectival or subordinative. Information is added to the base clause with modifying phrases, either bound to the phrase they modify, or as free modifiers. Cumulative syntax takes a base clause and adds information as free modifiers, usually in the end place but also at the start or middle of the sentence. Modifier phrases are either coordinate or subordinate to other phrases and can be mixed in the same sentence. Periodic or suspensive syntax withholds the base clause to the end of the sentence. Within either cumulative or periodic syntax, sentences can assume patterns; twinned, balanced, tryptych and so on.
I'll stop there. If you know your sentence structure you'll be wanting to correct me. If any of that left you bemused, seek the assisstance of Professor Landon above.
What does this have to do with voice? Well, the choices we make as we build sentences define the voice the reader "hears" on the page. If you rely heavily and routinely on what we have called above and exemplfied in this very sentence as bound modifiers, your writing will be complex, hard to process, arguably pompous, and make you sound like an academic. If your primary mode of adding information to a sentence is adjectival, you will unavoidably begin to stray into purple hued prose of pulp cosmic horror sylists like H P Lovecraft. If you demand simple sentences. If you hate complex sentences. If length in a sentence enrages you. Then you will stick to propositions. Then you will sound like a hardboiled crime writer.
Sentences aren't all of voice, but they are the heart of it. When I'm paid as a copywriter or journalist, I'm paid well because I can adopt the voice of the publication or business I'm writing for. I literally sit down and analyse how that voice is structured on the sentence level then imitate the style. Or in many cases define a style for places that don't have one. As creative writers we talk about "finding our voice", but that can often mean relying on a small set of sentence structures we have learned unconsciously. Often the best thing to do with the voice you have found is to break it, then rebuild it, the same but richer.