The antonyms for the phrase "be indolent" are to be energetic, active, diligent, and productive. Being energetic means having a lot of physical or mental energy and being alert and enthusiastic. Activeness means being in motion, being busy or engaged in various activities. Diligence refers to applying steady and persistent effort in one's work. Being productive means being efficient in getting things done and achieving results. All of these antonyms contrast with the concept of being indolent, which means to be lazy, apathetic, lethargic, or showing a lack of interest in exerting effort. It's essential to be mindful of these antonyms and strive to achieve productivity and success in our daily lives.