Do I have to specify the time when I say "How silly of me!" in the past?
Let's say I'm telling a friend about something silly that I did in the past, and I say:
How silly of me (it was) not to suspect that!
Is "it was" implicit in this case—since my friend understands that I'm telling him about a past experience—or do I strictly have to add it?
Please note, I know that I could say:
It was silly of me not to suspect that
But I want to maintain the first sentence structure.