The Earth's axis¹ is tilted² at an angle of approximately 23.5 degrees relative to its orbit around the Sun. As the Earth orbits the Sun, different parts of the planet receive varying amounts of sunlight due to this tilt³. This variation in sunlight causes the changes in temperature and weather patterns that we experience as seasons. When the Northern Hemisphere is tilted toward the Sun, it experiences summer, while the Southern Hemisphere experiences winter. Conversely, when the Southern Hemisphere is tilted toward the Sun, it experiences summer, and the Northern Hemisphere experiences winter. The transitional periods between these extremes are spring and autumn.

地球的自转轴相对于其绕太阳公转的轨道倾斜了大约23.5度。当地球绕太阳公转时，由于这种倾斜，地球的不同部分会接收到不同量的阳光。这种阳光的变化导致了温度和天气模式的变化，从而形成了我们经历的四季。当北半球向太阳倾斜时，北半球是夏季，而南半球是冬季。相反，当南半球向太阳倾斜时，南半球是夏季，北半球是冬季。这两个极端之间的过渡期就是春季和秋季。

英语: The tilt of the Earth's axis and its orbit around the Sun cause the four seasons.

汉语: 地球自转轴的倾斜和绕太阳公转导致了四季的变化。