 With Winsemius's help, Singapore attracted big oil companies like Shell and Esso to establish oil refineries in Singapore which became the third largest oil-refining centre in the world by the mid-1970s.The new direction that Singapore took demanded a skilled labour force to engage in her revised role of refining raw goods, as opposed to the traditional natural resource extraction industries of her neighbours.Its leaders decided early on that the population would need to be fluent in the English language, as they would be communicating and cooperating with expatriate employers or business partners abroad, and English was adopted as the medium of education for all schools.