Anything positive, inspirational, or famous can be used.
For example: The sea is wide enough for fish to leap, and the sky is high enough for birds to fly;
Don’t worry about having no friends in the future, because no one in the world will know you!
There is a road to the mountain of books, and diligence is the path, and there is no limit to the sea of ??learning;
When watering flowers, water the roots, and when making friends, you need to be heart-to-heart; etc.