Four Seasons, 四季, 四个季节, sì jì, sì gè jì jié。
Spring, 春, 春天, 春季, chūn, chūn tiān, chūnjì。
I like spring., 我喜欢春天。, wǒ xǐ huān chūn tiān.。
We participated in the spring fair., 我们参加了春季展览会。, wǒ men cān jiā le chūn jì zhǎn lǎn huì.。
Summer, 夏, xià。
Food must be refrigerated in summer., 食物在夏天必须加以冷藏。, shí wù zài xià tiān bì xū jiā yǐ lěng cáng.。
Autumn, 秋, qiū。
In autumn, leaves fall from the trees one after another., 秋天，树叶纷纷从树上掉下来。, qiū tiān, shù yè fēn fēn cóng shù shàng diào xià lái.。
Winter, 冬, Dōng。
This work will stop in winter., 这项工作将于冬天停止。, zhè xiàng gōng zuò jiāng yú dōng tiān tíng zhǐ.。
Four seasons refer to the four seasons that occur alternately in a year, namely spring, summer, autumn and winter, each for three months. The four seasons of the year are formed because the earth revolves around the sun. Due to the existence of the yellow-red angle, the annual change of the direct sun’s point moving back and forth between the north and south latitudes of the earth at 23°26′, which causes seasonal changes in the height of the sun at noon and seasonal changes in the length of day and night. The seasons change, thus forming the alternation of the four seasons.
In ancient times, the direction of the handle of the bucket was used to determine the alternation of the seasons, and the Big Dipper revolved in a circle. The current seasons are usually determined by the position of the earth on the orbit of the sun. The rotation of the four seasons reflects the changing laws of phenology and climate, including spring growth, summer growth, autumn harvest, and winter storage. Southern China (low-latitude areas) has more rain, more storms, and sufficient sunlight. The changes in rainfall, storms, and sunlight are obvious during the seasonal transition; in the northern areas (mid-latitude areas), there is less rain and less storms. The obvious changes during the seasonal transition are Temperature.
The evolution of the four seasons is not uniform throughout the world. The northern hemisphere is summer and the southern hemisphere is winter; the northern hemisphere changes from warm to cold, and the southern hemisphere changes from cold to hot. The length of day and night and the height of the sun have periodic changes in different seasons. When the earth is in different positions of the revolution orbit at different times of the year, the solar light received by various places on the earth is different, and the heat received from the sun is different, resulting in seasonal changes and differences in cold and heat. The four seasons on the earth are not only periodic changes in temperature, but also periodic changes in the length of day and night and the height of the sun. It affects or determines the movement rhythm of many things in the earth’s environment, especially the most obvious biological adaptation. Seasonal transition covers many aspects such as climate change and phenological change. The cyclical changes of the four seasons also indicate the development process of things: spring sprouts, summer growth, autumn harvests, and winter storage.