Trying to add multiple formulas in one cell

I'm very new to Google spreadsheets and I'm trying to add muliple formulas in one cell. This is my code so far, I'm not very good at formulas.

={SUBSTITUTE(C:C,"wd","Web Development"), SUBSTITUTE(C:C,"ch","Chores")}

This is one working equation if that helps:

=SUBSTITUTE(C:C,"wd","Web Development")

Thanks!