Meaning: This means the visible mass of water droplets or ice crystals suspended in the atmosphere moved along smoothly and gently above the earth at a leisurely pace.
Choice of Words: Drifted is the past tense of drift, which means to move along smoothly and gently. Cloud is a visible mass of water droplets or ice crystals suspended in the atmosphere. Sky is the expanse of air and clouds above the earth. Slowly means at a leisurely pace.