"Ella está escribiendo."
Translation:She is writing.
Regarding this particular verb form, is there a time when only this will be used? Or can one alternate between the simple indicative present and this and have the sentence mean relatively the same (besides the emphasis on now with this verb form). Because I know in English "She writes" is way different than "She is writing", and in English speech the "-ing" form is far more common. So, basically what I am asking is, is this verb form used exactly like English?
A good question! In my limited experience, the gerund form was used for something in progress -- "I am writing that computer program. Well, maybe not this instant, so don't look over my shoulder." Perhaps "escribio" means I actually am doing that right now? Hopefully a more knowledgeable person than me will reply!
Estar + (participle) = present progressive (you are in the process of doing it right now.)
Present indicative = simple present (this is more or less used how -ing is in English, it is in the present but it is not necessarily in the process of happening.)
Ex: "Ya tomo agua (I am drinking water now)" "¡Estoy leyendo! (I am reading!)"