The sound that was not a sound, heralding the opening of a major gate, intensified.

As large groups of protesters poured into the square the sound would intensify like a wave crashing on the beach.

The sounds of fighting quickly intensified and then died away.

The scraping sound intensified, but a foot or two further and the body of the truck would be safely through.

The sound of his voice intensified and she looked up, startled, to see that he was actually standing on the broad sill of the window.

The sounds of Worf's deep breathing intensified, but he did not respond further.

A door at the far end of the bar opened to admit two men, and the sound of ringing telephones intensified.

The sounds of the bridge had slightly intensified.

A few moments later the sound of disruptor fire intensified against the door, which was glowing red in a number of places.

The teen-agers were gone, but those creaking sounds from the attic intensified.