I had heard the sound of their engine for some minutes, behind us.

The sound of their engine came back to them across the dark water.

It was difficult to hear anything over the sound of their own engine.

Then I heard the sound of a large engine in the distance.

The sound of an engine coming closer said it all.

The sound of an engine behind the building drew him to the window.

Suddenly there was the sound of a powerful engine outside the door.

Moments later, even the sound of his engine was gone.

The low sound of an engine filled the silence between them.

In a little while, the sound of its engine faded on the night.