She wouldn't have thought it possible, but his expression darkened further.

He straightened up from the image, and his face darkened even further.

At least it seemed unlikely anything could darken the day further.

Her mood darkened further when she tried to play the violin again.

The intense yellow quickly turned orange, and then darkened further.

He was flushed with amusement, but his skin darkened further at that.

His dark face darkening even further, the pathologist said, 'Never seen anything like it.

It darkened further with the news about the missing vid record.

And global warming has further darkened the cloud over coal.

Gradually, the sky darkened further and they felt the pressure of lowering clouds.