Complex sentence: Of erratic temperament, she could indulge in life's pleasures, and gradually developed a reputation for hard-living; some would argue that her lifestyle took a toll on her voice, and indeed on occasion she could plainly be over-tired and out of form.
Split into simpler sentences: Of erratic temperament, she could indulge in life's pleasures, and gradually developed a reputation for hard-living. Some would argue that her lifestyle took a toll on her voice, and indeed on occasion she could plainly be over-tired and out of form.