If you want to be strong, be persistent. Enduring strength does not come in an instant, but is steadily built over time.
If you want to be strong, get in the habit of taking action. The strongest people are those who act while others only talk or wish.
If you want to be strong, be humble. Put your focus on doing, rather than worrying about getting credit.
If you want to be strong, be joyful. When you enjoy what you're doing, you are far more effective.
If you want to be strong, be yourself. The real strength you have is in the authentic person you are.