This image was submitted by Brook Power taken with Digimax V70/a7, at 1/125 sec, f/2.7, ISO 75. Brook took this of her sister, silhouetting her with a fish in the background. There is enough of the girl's face to make a nice silhouette. The bubbles in front of her add a nice touch. The fish is a little dark but let's focus more on improving the composition. Consider making this a vertical image, between the bubbles moving up in the frame and the fish above her head this could make a nice start to a vertical photo. Also try to keep your subject looking into the frame, there are times this is not as important but in this case your sister's line of vision looking into the corner draws your viewer's eye down to the corner and there is nothing there, their view takes them out of the image. If she was turned around or looking up at the fish this would be a stronger image with some sort of connection. Brook this is a nice start, you saw something different from the ordinary image and tried to make something of it. Unfortunately both the fish and your sister are heading out of the frame, leaving the image with nothing for the viewer. Keep practicing and keep looking for those different images, use the basic photographic rules of composition for a starting place.