Quote:
Originally Posted by aleCcowaN
I have  forgotten the substantive verb "ser" -just a minor detail-
han sido divididas (not "han sidas divididas"  ) |
I take you mean you
had forgotten, pluperfect.
Just a remark that there is no reason why a participle after haber should inflect, hence your "han sidas
" example, but
ser and
estar do require agreement. There is a parallel here in French, where active past tenses conjugated with avoir do not inflect, but those with e^tre do inflect.