By the time he and Clemson chatted later in the day, his mood had darkened considerably.

The stone has darkened considerably in the course of time.

The bow window had already darkened considerably, trying to filter out the inferno ahead of them.

The work has darkened considerably over the course of time.

All the wood has darkened considerably, and we would like to lighten this wood.

There is no respite from the economic gloom, which has darkened considerably.

Even with this stratagem the blue of sky and the green of palm trees is darkened considerably.

By the time Tom had signed off, the sky had darkened considerably.

The sky had darkened considerably and the wind was whipping up the sand into little tornadoes.

Since being exposed to the air in the past several decades, cinnabar frescoes have darkened considerably.