1. La Mansión del Inglés is a very comprehensive website. It covers
many things connected to learning English.
2. My parents were always very understanding when I was growing
up. Even when I shaved my head and joined a religious sect.
3. Pepito has a very comprehensive knowledge of the pubs and bars
in the city of Madrid. He always knows the best place to go.
4. I apologise for using office equipment for my own personal projects,
and I think it's very understanding of you not to tell the manager.

Understanding - comprensivo (sympathetic, compassionate)
Comprehensive - completo, amplio (complete)