steadfast
/ˈstɛdˌfæst/
marked by firm determination or resolution; not shakable
中文释义：坚定的；忠诚的
She remained steadfast in her commitment to environmental protection.
她始终坚定地致力于环境保护。
The steadfast support of his family helped him overcome difficulties.
家人坚定的支持帮助他克服了困难。