阅读下面短文，在空白处填入一个适当的单词或括号内单词的正确形式。

In Winter, Arxan, a city in northern China becomes 【小题1】 world of ice. Its rivers become 【小题2】 (freeze) all except one.

Upstream of the Khalkhyn Gol River, there is a stretch around 20 kilometres in 【小题3】 (long). Even in winter, when the air temperature 【小题4】 ( general) drops to minus 40 to 30 degrees celsius, this section remains ice free. People call 【小题5】 the Unfrozen River. Its secret lies deep beneath the river bed, 【小题6】 the river passes over an area 【小题7】 (allow) the river water to stay above freezing point. Therefore, it remains ice free. During the harsh winter, it even becomes a spa for animals.

A group of cattle 【小题8】 (see) strolling along on the river bank. They can’t wait 【小题9】 (walk) through the water. 【小题10】 (look) closely and you’ll see steam rising from the surface of the river. Such a nice warm bath! Let’s leave the cattle to enjoy it!