I don't find this one hard at all. The words have different connotations in the English language, and their game use matches those connotations.
I can see how it might be difficult for a non-native speaker of English, though.
Ouch, haha.
I'm gonna tell my players to "fix their f-ing English" (next time someone messes it up) I'm sure they will appreciate it, hehe.
I have a few players that are not that great with it, but I don't feel it's a lack of understanding English as much as it has to do with the quick pace of the game and stumbling over the similarity of the words - you have a bunch of things on your mind and this one gets jumbled from time to time.
I would say this is a pretty typical example...
PC1: "So I move here, I'm not sure between these powers... and let's see... wait... blast is which again?"
PC2: "adjacent box"
PC1: "Ohhh, right, duh"
...it's a "thinking out-loud" issue most of the time I think (in our case) ...you could say that if they were to stop and think about it visually (slow down a bit) etc, it makes sense, but in the heat of combat when things can get pretty fast-paced, it's forgivable and not something I would associate with poor English (at least in our situation).
I know you aren't trying to say anything degrading about people's use of the English language, or make fun of anyone, but you
did effectively say it should not be an issue unless English is a second language - and since it can be an issue with people I know whose primary language is English, it makes me wonder what the next conclusion would be - perhaps they are not the brightest guys around?, which would be funny because they are (mostly) highly educated college grads who make me feel like the slow one in the bunch (which I am)
Anyway, I can't wait to talk s--t to the next one to mess it up - I'm gonna blame you by the way, hehehe.