wēn / dù / jiàng / dào / níng / gù / diǎn / yǐ / xià / hòu / hú / miàn / kāi / shǐ / jié / bīng温度降到凝固点以下后,湖面开始结冰。After the temperature fell below the freezing point, the surface of the lake began to freeze.