保持天真善良的英语短句有：
1. Keep your heart pure and intentions honest.
2. Embrace the beauty of innocence and kindness.
3. Stay innocent and kind, no matter what.
4. Never let the world harden your gentle spirit.
5. When I was young, I was innocent and kind, and I remain so to this day.
这些短句鼓励我们在任何情况下都保持一颗纯洁善良的心