1. A careful, thorough, and persistent way of doing something with attention to detail and consistent effort
She completed the project in a diligent manner, checking every detail.
Ela completou o projeto de forma diligente, verificando cada detalhe.
2. The quality of being attentive and conscientious in one's work or duties
He approached his studies in a diligent manner despite the challenges.
Ele abordou seus estudos de modo diligente apesar dos desafios.