.ron
steis
ste
mos
es
o
ó
í
ué
(?<!u)é
(?<!st)e
(?<!ro)n
(?<!.is)s
(?<!mos)s
(?<!eis)is
(?<!ste)is


##</code><code>##

.ron
steis
ste
mos
es
o
ó
í
ué
é
e
n
(?<!.is)s  ## maybe meant (?<!.i)s
(?<!mos)s  ## maybe meant (?<!mo)s 
(?<!eis)is ## maybe meant (?<!e)is
(?<!ste)is ## maybe meant (?<!ste)is 


##</code><code>##

steis
.ron
ste
mos
es
ué
o
ó
í
é
e
n
s


##</code><code>##

steis
.ron
ste
mos
es
ué
[oóíéens]