having dinner, eating dinner
Ayer, cuando mi hermano llegó a casa, yo estaba cenando.
Yesterday, when my brother arrived home, I was having dinner.
Estábamos cenando cuando sonó el teléfono con la noticia inesperada.
We were having dinner when the phone rang with the unexpected news.
Cuando estaban cenando, yo estaba con el postre.
While they were having dinner, I was with the dessert.
— Uno de los nuestros (1990)
En ese momento estaba cenando.
I was having dinner at that moment.