वायु प्रदूषण

覆盖；在某物上方或周围散布。

To hit forcefully or with great impact; to strike.

Food chain; a hierarchical series of organisms each dependent on the next as a source of food.

At a slow pace or speed; slowly.

By chance or without intention; accidentally or suddenly.

天空

由数百万或数十亿颗恒星、气体和尘埃组成的系统，通过引力结合在一起；星系。

Relating to a galaxy or galaxies; galactic.

与天空或外太空有关的；天体的。

通常在雷暴期间发生在天空中的闪电。