Minecraft enchant?

I wanted to get a Sharpness III book, but since it was a level 30 entchant, the book now also includes explosion protection and breathing. I can't do it on my sword now. What should I do with it now?

You can still enchant it on your sword. Breathing and explosion protection are then simply gone and you only have sharpness III on it.

Thanks, it looked like this at first so it wouldn't work.