Comment block text going across the screen

I’m trying to figure out what is going on with my comemnt block, but don’t seem to be gettign very far.

I’ve figured out how to keep the comment blkock to a certain size in pixels, but I have doejn a etxt on long lines of words, and they shoot across the screen.

Is there a way to stop that happening?

Also, is there a way to put in a percentage for the comment block, and have it as the percentage of that div?

This is the site:

https://test.wpsingle.com/?p=1

Don’t worry about the colours, that’s for me testing. The green is the fdiv and the red is the comment block code.

Thanks