The sky brightened slightly, but the sun never really came.

The sky had brightened in the east and the sun was about to rise.

So now they sat there watching the sky gradually brighten.

The eastern sky was brightening, and the day had begun.

Outside the hurrying car, the sky was brightening in the east.

The sky was already brightening when they came out of the bus terminal.

In the east the sky brightened as a signal to the rising moon.

The sun was rising, the sky brightening from its deep night blue to a pale gray.

The sky was brightening outside and the bracket clock said seven.

We talked as the sky brightened into true morning.