<classify> Zazikhona izindlu zangasese kweyamandulo i Egypt, Persia neChina. Ku khanyiso lwama Roman , izindlu zangasese zaziye ngamanye amathuba zibe yinxalenye yendawo zokuhlamba zikawonke wonke apho amadoda namabhinqa babekunye bexubene.  <topic>: how things work, flush toilets 