Answers
Dec 07, 2012 - 07:08 AM
Remember that the simple past tense of "ser" is the same as the past tense of "ir". So, "When was (it)" does translate as "Cuando fue" assuming it is past tense of "ser" and not "estar." Although it is sometimes difficult (especially me) to know when to use "ser" or "estar" I think "when" statements or questions usually use "ser".
Dec 09, 2012 - 05:46 AM
The days of the week are used with ser not estar ie. hoy es el domingo not hoy está el domingo, so the same applies for past tense, fue el domingo. I can't really remember the grammatical reasons for these things but I can assure you both are correct, cuando fue as well. It is not an error with the program.