application, assiduity, assiduousness, bulldog tenacity, concentration, constancy, continualness, continuance, continuation, continuity, decisiveness, diligence, dogged perseverance, doggedness, endurance, energy, engrossment, extension, fidelity, force, fortitude, guts, gutsiness, hardiness, heartiness, indefatigability, industriousness, industry, insistence, insistency, intestinal fortitude, lengthening, loyalty, lustihood, lustiness, maintenance, might, mightiness, obstinacy, patience, patience of Job, permanence, perpetuation, perseverance, persistence, persistency, pertinaciousness, pertinacity, plodding, plugging, potency, power, powerfulness, preoccupation, progress, progression, prolongation, protraction, pursuance, relentlessness, repetition, resolution, robustness, ruggedness, run, sedulity, sedulousness, single-mindedness, singleness of purpose, slogging, stability, stalwartness, stamina, steadfastness, steadiness, stick-to-itiveness, sticking power, stoutness, straight course, strength, strength of will, stubbornness, sturdiness, sustained action, sustenance, tenaciousness, tenacity, tirelessness, toughness, uninterrupted course, unremittingness, unswerving attention, vigor, vigorousness, vitality, way

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