Oh gosh. We're just going over this in class actually. There are more reasons to use "Ser" than there are to use "Estar", which are; (For Ser) 1) Physical description, personality and character, nationality, race, gender, profession, origen, and anything else pertinent to your Identity 2) Things which "Take Place" or "Occur": Dates, days, seasons, time, events, concerts, parties 3) What things are made of 4) Possession Estar is used with 1) Feelings/emotions, physical conditions or appearances, civil status (married, single, divorced, dead) 2) Location of things and people (not events) 3) Present Progressive tense (the immediate "-ing" form) Hoped this helped!!