Geylang road is the red light area in Singapore;)
You can not buy or sell chewing gum but prostitution is legal in Singapore!

A quiet part of Singapore to visit: Changi Village for the famous nasi lemak, strolls by the beach and perhaps a bum boat ride to an offshore island (e.g. Pulau Ubin). One of the places you might want to visit is Chek Jawa (visit the Singapore Parks website for info)- a conservation area with a variety of marine life.