1.   As his relations carried him off to be buried, the sky suddenly darkened and the heavens opened.

2.   Straight away a great flock of wild crows came flying towards her, enough to darken the sky.

3.   But even today an active volcano, Ol Donyo Lengai, can darken the sky with violent eruptions, adding new powder to the Serengeti.

4.   As a filthy haze from vast Indonesian forest fires continues to darken the sky across seven Southeast Asian nations, illness, ecological destruction and economic hardship are growing.

5.   A thunderstorm was darkening the skies as I approached Luzane and fingers of lightening were touching the still bright, empty meadows to the west.

6.   He muses on the now-extinct passenger pigeon, whose flocks once darkened North American skies for days.

7.   Ominous thunderclouds instantly darkened the skies.

8.   Only moments before post time, the skies darkened, lightning flashed only a few miles from Churchill Downs and a strong rain began.

9.   Smoke from burning buildings and smoldering tires darkened the sky, and gunfire could be heard sporadically.

10.   Then the asteroid hit, darkening the sky with dust, filling it with acid rain, killing off most plants and wiping out the opposite birds.