Any RP post in the Meeting Hall should be at least a small paragraph. You should be able to get at least 3 sentences without even trying. If you can't, you probably need to make your way over to the White Scenarios forum and take the pre-scenario training there.
A post doesn't have to be - in fact shouldn't be - just what happened right at that moment. Consider your character's senses. Consider your character's thoughts. What else is going on besides just what you did?
She heard the blaster bolt sizzle faintly as it passed through man's chest. He hit the ground with a soft, but very final thud. The smell of burnt flesh filled the air and stung her nose. She stared at the body a moment in disbelief, before her eyes flickered up to the aggressor. Rage filled her. Many people died daily, it was true, but did there have to be more senseless killing? She jumped to her feet, hands clenched into fists as she confronted the one with the still-smoking blaster.
"Why did you do that? It makes no sense! He didn't do anything, so why kill him?"
If your character has seen a lot of death, you can insert some memory of a person you saw die a similar way, or the way the eyes of past corpses have stared blindly, like this one. If it was a bladed weapon instead of a blaster, describe the way the light caught it as it struck, or the sound of the blood dripping slowly from the blade to the floor. What material is the floor? Does it have a sharp, metallic ring? A dull tapping on wood? Or a very soft sound as it drips onto dirt/sand, that soaks up the blood and changes the shade of the ground below the murder weapon? And then, of course you can smell the blood. The smell of iron, so strong you can almost taste it, like when you bite your lip, or suck a small cut on your finger...
Do more. This is not the fourth grade "What I did on my summer vacation" assignment. =D