[William Tell]

forgotten man said: 14) “If I was” instead of “If I were”

I was taught to say:
"If I was on fire, I would burn, but if I were you I would just ignore it."

The distinction is that being on fire is possible. My being you is not possible. Several years ago I tried to verify this usage but ended up just confused. What is your rule?

[Fundamentally Fair]

http://www.quickanddirtytips.com/education/grammar/subjunctive-verbs

[forgotten man]

I would say “If I were on fire...” because I am not on fire and have no intention of setting myself of fire. If I am on fire please throw water on me. I need to look that one up in my grammar book.