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ambition; aspiration; desire to improve oneself
彼はとても向上心が高い。
He has a very strong desire to improve himself.
新入社員の彼女は向上心に燃えている。
The new employee is burning with ambition.
その向上心を持ち続ければ、必ず成功するだろう。
If you keep that ambition, you will surely succeed.