Don't use this archaic style of English.
Are these sentences correct:
1-I couldn't see him for standing in the shadows.
2-For standing in the shadows, I couldn't see him.
(I couldn't see him because he was standing in the shadows.)
3-I couldn't hear the phone ring for having headphones on.
4-For having headphones on, I couldn't hear the phone ring.
(I couldn't hear the phone ring because I had headphones on.)
Gratefully,
Navi.
Don't use this archaic style of English.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.