On the first shot the sky is a little blown out; expose for the highlights next time. Also the bottom left edge and right corner both have some distracting junk with the concrete and the bush. Corners and edges will kill your shots if they're not clean. Watch your corners and edges always.
Second shot would look better if the horizon was leveled and if the central boat was a little more off center, heading more "into" the frame. Still, it's a decent shot, just needs some tweaking.
Third shot has a distracting element on the top edge that's really hurting it. The boat should also have some room to be moving INTO the frame, not out of it. This is just a basic rule of composition.
Three things that will help: 1. Every photo needs a clear subject. 2. Watch your edges and corners before taking the shot and, 3. Learn to use the
Rule of Thirds when composing.