Image taller than post text problem

Hey all, new user to WordPress. My site’s theme is a modification of the standard WP theme. I notice that if I create a post with an inline image that is taller than the text, then the image will collide with the next post. I use the alignright class for the image, which puts it in the right place, but doesn’t “clear” the image for the next post.

The way I’ve worked around that is to add <br> to the text so that it is at least as tall as the image, but that’s not a very satisfactory solution. I use the alignright class for the image, which puts it in the right place. You can see a couple of examples at:

https://zawinulonline.org/2006/10/

The first and third posts show what I’m trying to achieve without resorting to <br>’s.

Anyone else run into this problem with the standard theme and come up with a better way to address it?

Thanks.
Curt