Okay, we've dealt with the basics. First, you spell check, then you grammar check, and finally, you give it to someone else. This is a pretty good way to start improving. Nevertheless, there are probably some of you who already do all that, and still you're not getting the response you want. This is where Dr. Merlin hands out advice on style (kindly ignore the mismatched socks and the holes in the blue jeans -- I'm a chemist, not a fashion consultant).

One of the things that throw professional editors off a story is the switching of point of view in the midst of a scene. I'm serious; this is the major gripe I've seen from editors for magazines, books, anything. It's jarring to be looking out of Captain Janeway's eyes one minute, and then to be suddenly inside the head of Queen Titania, staring back at her. Humans simply don't think inside two heads at once (although I've heard Betazoids can). Also, the only way for the following line to be true: 


     Everyone realized at once that the giant space alien was just
     Data's cat.

is for "everyone" to be a Borg.
In order to keep your scene flowing, stay in one point of view at a time, and have a definite switch (with blank lines or some other delineation, rather than just the closing of a paragraph) between characters. You can have as many points of view as you want otherwise, but make sure you keep them separate (unless, of course, the effect that you're going for has to do with not know who's thinking what, at which point you can basically skip this bit).

One last thought on style: keep it consistent. Please. If you want to tell a story from the first person POV, fine. If you want to use present tense, perfect. Keep it there.

Merlin's Personal Peeve Regarding Style Part 1: Don't have two characters think or say the exact same line in your story, unless it's intentional.

Merlin's Personal Peeve Regarding Style Part 2: Write your entire story, then post it. I can't say how many times I've started out writing one story and ended up writing something completely different. I'm not necessarily displeased with the results, but then I'll usually have to go back and change the beginning to make it fit. You can't do that if you're writing and posting in parts. Again, it's just my own personal opinion on the matter, and one you're more than free to disregard.