The most important stage of life is youth. If you don't work hard when you are young, you can only regret it for a lifetime when you are old.

The most important season in a year is spring, which is the season of cultivation. No cultivation in spring, no harvest in autumn.

The most important time of the day is morning, when people are most awake and the rising sun and air are freshest, so this time is the best time to do things.