2. Short-lived
3. "Listen to the teachings of latecomers and don't be a puppet of your own actions. Don't be friends with the flying dead, and don't be enemies with the still. " It means don't stay on yesterday's teaching. Only by conquering the fleeting time in front of us can we seize the best opportunity of life and avoid all troubles.
Time is fair and fleeting.
I hope my answer is helpful to you ~ ~ ~