Need help with 2 things

[killersam19]

So i tried making a cave in a cliff on a lake and i asked my wife if she could tell what it was and she couldn't, so how can i draw it better to make it more distinguishable. Sketch (2).png And i also tried making a crevasse and i think the top looks good but near the bottom not so much. desert.png

[Falconius]

With the cave you could detail the water or floor going inside it. And for the crevasse kind of the same thing, draw in an indication of floor.

Example:
example_001.jpg