I'm not sure how to translate x1, x2 and so forth, but I'm sure there exists a standard convention for it.
lo pamoi sumti goi xy ce lo remoi sumti goi ybu ce li'o ?
Just a tip.
mi'e darves
If you're going to use that system, you may as well start with a bu. -- Or you can use xy boi xi pa, xy boi xi re,
etc. Or maybe ko'a, ko'e, ko'i, &c. mu'o mi'e komfo,amonan