I know how to convert from infix to prefix or postfix. But how do you wrap parentheses around this problem:

a / b * c - d + e * f + g

This is how I think it is accomplished:

( ( ( a / b ) * c ) - d ) + ( ( e * f ) + g )

Am I doing something wrong? I am wraping parentheses around terms left to right using P E MD AS.