“斗心”翻译成英文。

fight 斗志
There's not much fight left in him now.
他现在已没多少斗志了。

心 可以用 heart 和 mind

参考

他斗心很强 he has a heart in fighting.
她不会失去斗心 she will never lose her strong mind

要单纯就斗心一词做出翻译，需要参照上下文明确其特定语义，才能做出参考答案。

There's not much fight left in him now.