Please... please please please...
Use a dictionary!
Use a thesaurus!
Find some nice grammar websites and USE THEM.
I beg you, for the love of Eurypides' pen!
I s'pose I may be able to forgive you for being a casual writer and only posting one story for fun, sure... as long as it can be read, that's great!
But if you're going to be writing stories consistently... please, I beg of you, approach it with the reverence that the art deserves.
I'm not even talking about cliches or whatever... just make it proper English and immediately the story is many times improved.
Once you've accomplished that, once you sound like you know what you're talking about, then you can start developing your own voice and experimenting...
But please, it really isn't that hard to learn. I'm not even holding it up to college standards.
Trust me, it really works.
Oh... and... for the love of Shakespeare... please don't overuse the thesaurus. That's almost as bad as not using it at all!