BRAVING the harsh wind and rain on Hong Kong's coldest day in 17 years, four boys refused to give up their pursuit of the Duke of Edinburgh's silver award. Ho Yiu-man, Hung Chi-fat, Pang Kam-sing and Yuen Chi-wang of Lee Wai Lee Technical Institute were among the 165 awardees who had achieved success in all four sections of the scheme: service, expeditions, skills and physical recreation. ''It was really an unforgettable training,'' said 19-year-old Yiu-man. ''We will always remember how we shivered in the cold during our expedition.'' Yiu-man and the other boys spent three days in Hoi Ha, Sai Kung, completing an expedition during the coldest period of December 1991. That year, days after the territory enjoyed its warmest Christmas in 15 years, temperatures plunged suddenly, dropping from 24 degrees Celsius to 4.7 degrees Celsius by December 29. ''Scores of visitors flocked to Tai Mo Shan, where the recorded temperature was minus 3.0 degrees, to catch a glimpse of the frost and icicle-covered plants on the hill slopes, but we were forced to sleep out in it in order to finish our expedition,'' Chi-fat, 21, said. ''That night we stayed in the tent but we could not sleep because of the bone-chilling cold. It was raining too. Our shoes and clothes were all wet so it seemed even colder.'' The four boys said some of their team members could not bear the cold and left the camp. But they did not. ''I thought of giving up and going home to sleep in my warm bed but the hard work I'd already done spurred me on. ''Besides, we are boys and should not be defeated by the weather. We encouraged each other and we succeeded,'' said Chi-wang, adding that they ate as much food as they could to keep warm. Kam-sing said he felt their success not only showed they could defeat the cold but also trained them to be more mature and stronger. ''You will never know what you can do unless you try,'' he said. Officiating at the presentation ceremony, Major-General J. P. Foley, commander of the British Forces, encouraged the awardees to continue their involvement and strive for the gold award. This year's awardees came from 13 operating authorities. The Vocational Training Council topped the performance list with 56. The Duke of Edinburgh's Award Scheme, introduced in Hong Kong in 1961, aims at providing young people with leisure activities and promoting personal growth and development.