阅读下面短文，并用英语回答问题(请注意每小题后面的词数要求)

It's December. The weather is snowy and really cold in the north of China. You can see many children playing with snow. Some of them are making snowmen. Some are skating on the river, because it's so cold that the water in the river freezes (结冰). It's a white world. How beautiful! But in Australia now, the weather is hot. Many people go swimming in the sea. They are having a good time. Jim and his friends are playing soccer near the sea. The sunny weather is really cool to them. They want to swim after playing soccer.

Why are they swimming in December? It is winter, isn't it? Yes, it is in China. But it isn't in Australia. That's because we, Chinese and Australians , have different seasons (季节) in a year.