Why is Mai Huang one year old?

This sentence reflects the rapid change of things.

When the wheat is about to ripen, it will soon turn yellow in one day, especially in North China. As long as there is a southwest wind one day, many wheat will suddenly mature. A rest here can refer to an afternoon or a night. Describe the speed at which wheat ripens.

People's aging is a gradual process, but there is a phenomenon worthy of our attention, that is, between the ages of 40 and 60, if you live a happy and peaceful life, you will maintain a relatively stable state for many years. Still older is slower. When people encounter diseases, they will soon get old after a short period of time, and there is also the role of psychology, especially after middle-aged people encounter mutations, they will soon get old, their hair will turn gray and become haggard, so people are said to be one year older.

So this sentence is a sentence that describes things changing quickly and changing greatly in a short time.