Consider the following premises. For all x_12, if x_12 were happy, then x_12 is an electrician. John is an electrician if and only if John is happy. Can we infer the following from them? If John were an electrician, then John is happy.
 From the fact that for all x_12, if x_12 were happy, then x_12 is an electrician we can infer that if John were happy, then John is an electrician. Finally, from the fact that John is an electrician if and only if John is happy we can infer that if John were an electrician, then John is happy. Therefore, the answer is yes.