"Your train is here."
Translation:Tu tren está aquí.
The simplest way I remember is that 'Es' is used for permanent situations where as 'Esta' is used for temporary situations. 'Eso es un perro':'That is a dog' this is permanent because it will always be a dog, the state of being a dog will not change. 'Tu tren está aquí':'Your train is here', this is temporary because the train will not always be here. It will eventually move.