下定决心做某事用英语怎么说

如果你想用英语表达“下定决心做某事”，你可以使用以下短语：

- Make up one's mind to do something

- Determine to do something

- Set one's heart and soul to do something

- Resolve to do something

- Decide to do something

希望这些短语能够帮到你，如果你还有其他问题，请随时问我。