I usually enter racial slurs. Anything that uniformly distorted or obviously foreign (or math) is pretty much random.

yikes, is that even real?

You can hit refresh though.

Then again, I'm not sure how you would manage when you missed "entril".

You only have to enter the words that look like the one on the left (with that back-drop kind of effect and rough edges). The second word, which usually has sharper edges and most often special characters (or **** that's not even English) is, so I've been told, part of their word-filling database, and they collect inputs to decide on how a particular word image should be most likely input by the user.