La. La. La.

Today’s topic will be sentence length.

This is something that beginning writers really underestimate. Sentence length and structure has a huge impact on the flow of the scene. It’s not something that we really have to go into a lot of detail for, as it’s something best learned by observation and experimentation, but let’s talk basics here.
Firstoff, long sentences does not equal intelligent sentences.
It really irks me, you know, because in my last workshop class our teacher really put a lot of pressure on these classmates of mine, many of whom were beginners to writing, and expected them to write something worthy of a Pulitzer. The end result was that almost every paper written for that class was riddled with long run-on sentences. Why? Because they thought that long sentences would impress the teacher.
Quite simply, one sentence equals one idea. Remember this always. Short, concise sentences are just as intelligent as long, well-composed flowy sentences.

Short sentences can be used to give a stilted feeling to a paragraph. Used incorrectly, it makes the paragraph hard to read. Used in the right context, however, it can used to do all sorts of things—I’ve seen it used to express how awkward a situation was, how boring a dinner party was, or even on a couple of occasions it gave a slowed-down, panicked feeling to a scene that was happening all too fast.
Read around. Play with different ways to use short sentences.

Longer sentences have a much broader range of uses, mostly because they sound more natural. They generally have a better flow and make the paragraph as a whole easier to read. If you’re not going for a stilted feel, go with these. However, beware of sentences that are too long. They can easily become run-ons.
Run-ons are the devil.
Generally you should go for medium-length sentences. Not too long, not too short.

Incidentally, run-ons can be acceptable in character dialogue, provided that it’s clear that it’s intentional and it suits the character. People can naturally speak in run-ons, so if you have a character who might have a habit of trying to say too many things at once, run-ons might naturally appear in their speech.
However, run-ons have no place in narration.

Like I said, this is something that one needs to experiment with and observe to fully understand, but I hope I’ve at least given a decent explanation. It’s a bit of a squishy subject so I wasn’t sure how to describe it well…