The door hummed quietly to itself, and then swung smoothly open.

As it happened, the train was waiting, humming quietly, and left right on time.

After a moment it hummed quietly to indicate its befuddlement.

The flycycle hummed quietly to itself a few feet away.

He proceeded to hum quietly a Christmas carol of his own.

Beneath them the exclusive art foundation hummed quietly with life.

The car's engine hummed quietly as they drew up to the traffic lights and stopped.

Humming quietly she entered her refreshing room and prepared for the day.

The computer on the desk hummed quietly to itself.

Humming quietly to himself, he looked over the edge and took in the scenery.