[Beatrix]

Could someone please explain when we use for and when about?
It's still unclear to me, or, at least, I can't provide an explanation that sounds good enough.
Are they completely interchangeable?

A million thanks in advance.

[susan53]

Well, first of all I'm sorry for (!) taking so long to reply to this but it's my busiest period of the year at work.


Be sorry has two meanings : a) empathise and b) apologise

1. When it means empathise you can be/feel sorry for someone - eg I'm (or I feel) really sorry for John. First, the accident, then he lost his job and now his house has burned down.
If you want to specify the event, it will always be with "about" :
John, I'm really sorry about your house.

2. If you apologise for something, on the other hand, then it means you take responsibility for the event. You can still use "about" : I'm sorry about the delay in answering your question but the apology sounds "deeper" (and perhaps slightly more formal) if you use "for" : I'm sorry for the delay in answering your question.

So:
- to express empathy : sorry for someone/sorry about something

- to apologise for something (when you are taking responsibility for the event) : sorry about for casual apologies /sorry for for more genuine expressions of regret (or more important problems)

[Beatrix]

I couldn't imagine a better explanation.

Thank you so much, Susan!