An example, for those who need one:
"I had just asked a very important question, and then, during the answer, the fire alarm went off!"
It's only a phrase, not a complete sentence, so that may be why it is confusing. But then a lot of sentences/phrases/etc are confusing without a context.
For example, one person asks: "When should I interrupt him?" = "Quando eu devo interrompê-lo?"
It is a prepositional phrase. It would be highly unusual to see this taught in isolation in any well-developed language course.
There must be more idiomatic translation. Could it be one of those things that doesn't translate directly into English. Maybe somthing like "in answer to (the question)" or "(waiting) for the answer". In my native English it just doesn't make any sense"
This is what I was commenting: people with great lack of immagination... which has never (or very little) read in their life. Anyone with a little culture could think of 10 sentences using this phrase in less than a minute.