Every single circuit must have a neutral wire to return the
supply to the main, without neutral the circuit will not be
complete, thus ur light or appliances will
not function.
A live and neutral is a MUST to complete a circuit. The
green/yellow cable can be excluded but at ur own risk.
I advise u to report the electrician to police.
Or u can try Energy Market Authority or Singapore Power.
CAll their customer hotline.
Neutral and earth is diff thing leh.