Don't be bashful! If you want comments, give comments. You don't need to be an expert photographer to express your opinion about the work of others. You don't need to go into great depth. A simple remark about cropping, composition, color, subject matter, etc. can be of just as much help to a budding photographer as an in-depth critique.
Action photos are some of the most exciting ones that we can create. The first thing you must decide is how you want to portray movement. Some kinds of action are best expressed by freezing their peak moments. You may want to use a fast shutter speed so that every detail is very sharp--a basketball player suspended in midair, or a skateboarder at the peak of his upward momentum. However, at other times you may choose to blur your subject intentionally with a slow shutter speed to emphasize the feeling of motion. Whatever way you choose to portray action, it’s fun to experiment with a variety of shutter speeds, vantage points, lenses and styles.