Translation:My grandmother was sad when my grandfather died.
Does the sentence use the word 'was' because 'ketika' was used? I am just wondering if it would change to 'is' if 'karena' was used: "Nenek saya sedih karena kakek saya meninggal." Would that become "My grandmother is sad because my grandfather died? Just trying to make sense of the way to use past, present. Thanks for any help