Oooh you are getting into this trouble of Ser & Estar, it's a peculiarity of spanish a little difficult to grasp because they are both translated as "to be". But I will try my best dear, let's schedule a session once Pino gets better =) ! jeje In short, "ser" is a permanent state and "estar" is for temporary conditions. For example, to be free as a permanent state and to be free at certain period of time. For the first you would use "Soy libre" and for the second one "Estoy libre"... like if someone asks you "Can you voice talk?" and you want to say "yes I'm free" the answer would be "Si, estoy libre" .. once you learn this, then learn all the conjugated times for each verb and there you go... but like I said, I'll give you further explanation in the coming days. Cheers GBU!

What about open your book?

Not an answer per se, but i try to Explain You With Some examples ... First, assume that the "Era" of that question comes from the verb "be" ("Era" can be used to speak of a period of time, like "Age". Now some examples, -"Ella era estudiante de medicina" (She was a medical student). -"Ella estaba preparada para partir" (She was ready to go). ERA is primarily used to describe something or someone in the past. ESTABA, on the other hand, is used to indicate how was that something or someone? in the past. -"El edificio era azul." (The building was blue). -"El edificio estaba en malas condiciones". (The building was in poor condition).

Era - Comes from the verb Ser... Used to describe things that dont change quickly, or things that only happened once. Examples: Ella era joven. ( She was young) Era is used because she can not become old in an hour or in fifteen minutes. It is a characteristic that is used to decribe the person or thing that only changes over a course of time. Estaba - Comes from the verb Estar... It is used to decribe things that someone was doing over a course of time. Example: Ella estaba dibujando ( She was drawing) the drawing that she did was continuous and that is what "aba" represents when it is at the end of any verb... Therefore it depends on what is being talked about and also how long the event took place, if it is continous or able to easily change then you use Estaba, if it is not continous ex. physical characteristics, or an event that a friend went to one time then you use Era. However if you attend the event every weekend then you would use iba (from the verb "ir") If you want you can email me and I can help you. I know grammatical spanish and it is easier to explain through speaking than to type it in order for you to understand :)

Para poder entender el uso de ERA Y ESTABA, tienes que estudiar los verbos SER Y ESTAR, que son verbos irregulares. ERA y ESTABA son la conjugación en Pretérito Imperfecto (Copretérito), de SER y ESTAR. Para una mejor información puedes ir a: http://www.bing.com/search?q=Usos%20de%20los%20verbos%20ser%20y%20estar.&FORM=WLETLB&PC=WLEM&QS=n