With floating images (refer to image alignment) the (break) BR tag has to be expanded. If you wish to stop filling the space next to an aligned image and start on the next line underneath the image, then a normal line break will not work - it will just break the line to the current margin alongside the image. A new paragraph will also continue wrapping the text alongside the image.
In particular, this sentence should be rendered beginning on the next line with the current margin alongside the image since it follows a BR tag that has CLEAR=none assigned.