if i were ... , i would ...

some times we think, if i was here i would help you, those sentences khan be write in formula below

If S +were + N, I would
which S = subject
N = Noun
in japanese language
もし＋N+なら、S。。。

look more this example below :
1. もし日本人なら、あなたに結婚することができるのに。　－mosi nihonjin nara, kekkon suru koto ga dekiru noni, - if i japanese people, i would marry with you.