Is there a user-friendly program that lets you diagram sentences on the computer?

Here’s a funny statement: I enjoy diagramming sentences. I find it fun to play with the English language and figure out how a sentence fits together. It’s like a puzzle. But enough about my odd hobbies…

All that writing and turning the paper and erasing and tearing the paper gets frustrating. I googled it a bit, but I can’t find quite what I’m looking for. I want a simple interface, and I want to be able to delete things (one program I tried didn’t have this capability). Is there a program that you’ve tried that works well? Am I missing something in googling it?

I also am known to procrastinate by “getting ahead in algebra.”