J'en ai besoin d'aide avec un traduction!

[Chaotic Overdose]

How would you say "How was that possible?"
I know that in present tense it is "Comment est-ce possible ?" but I need it in past tense.

[Super striker 9]

You would say ''Comment était-ce possible''.

[Chaotic Overdose]

That's what I thought, but I wanted to use regular past tense (a été)

[Super striker 9]

Then you would say ''Comment cela a-t-il été possible?''. smile

[Princeries]

Or "Comment cela a-t-il pu arriver ?", depending on the context, of course.
(As "comment cela a-t-il été possible" is correct but may sound a bit clumsy)

By the way, we say "J'ai besoin d'aide pour une traduction" wink

[Chaotic Overdose]

I'm not super duper french.
But thanks for the help.
I figured it out myself x]