The whole emphasis on this picture is her. She's the only thing going on and all your focus is on her.

There are things going on in the background, but the attention is pulled to the center of the painting where the horse and people are painted.

The yellow part of the painting is emphasized because it becomes bright against the dark blues of the sky and buildings. It really brings your attention to the left side of the painting.

The people are isolated into the diner while nothing is going outside. It brings your attention to the man sitting alone, then to how bare it is outside.

She is in the center of the page, so we automatically look at her. She becomes the focus.

This paintings brings out elements to the viewers eye. It has a lot going on, but you still focus on the colors and lines of the painting.

The apple brings your attention first, but then you realize they're are other things that do not belong.