steadfast constancy
unfailing constancy
constancy of character
A: Do you believe in the constancy of human nature?
A：你相信人性是永恒不变的吗？
B: I have seen great constancy in her devotion.
B：我在她的奉献中看到了极大的忠诚。
1) 忠诚，坚定
2) 恒心，不变
3) 稳定性，持久性
1. 忠诚，不渝
2. 恒定，不变
noun
1. The quality of being faithful and dependable; the state of being unchanging.
Synonym: faithfulness, stability, persistence