People bothered by noise from overhead aircraft shall hear a difference in the skies soon.为头顶上隆隆的飞机噪声所苦的人们，不久将从听觉上发现空中明显的变化。Air pollution is clearly visible in the skies over the city.空气污染在这个城市上空清晰可见。Vapors drawn from the sea mustered in the skies.海上来的蒸气聚集在空中。