He is a very determined and strong-willed person.

他是个很有决心和毅力的人。

《柯林斯英汉双解大词典》

Joseph is strong and determined. He's a tough person.

乔瑟夫很坚强、有决心。他是个意志坚强的人。

youdao

It is believed that ox's great strength can empower the small and weak, so the idiom "possessing the spirit of an ox" is used as a metaphor for a person who is strong and determined.

在人们的心目中，牛的强大足以让弱小者生畏，所以用“气壮如牛”来形容一个人的精神、气魄和力量。

youdao

Anybody who knows her history knows what a strong, determined and gifted person she was.

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