求翻译：商品房预售制度起源于上个世纪五、六十年代的香港。霍英东成立的立信置业有限公司一改现房销售模式，提出“预售花房”提倡分期付款。上个世纪九十年代，我国大陆房地产市场开始兴起，并将香港的销售模式引进来。1994年7月施行的《中华人民共和国城市房地产管理法》全面规范房地产开发，正式确立了商品房预售制度。是什么意思？

Pre-sale system originated in the last century, the fifties and sixties in Hong Kong. Fok Ying Tung Fong Properties Limited established a change in existing home sales model, that "pre-greenhouse" to promote installments. The nineties, China's mainland real estate market began to rise, and sales mod