そっけなく の訳語→ absently briefly brusquely carelessly coldly curt flatly hastily indifferently insipidly lightly matter-of-factly shortly simply tightly
事もなげに の訳語→ easily ever-ready nonchalantly
平然と の訳語→ calmly detachment evenly imperturbably unconcerned unmoved
冷静に の訳語→ calm clearly critically dispassionately rational rationally reservedly silently soberly