11.   The expanding and contracting of the vinyl siding, caused by temperature changes, are making those popping sounds.

12.   The original, which Nauman recorded on older equipment, includes popping sounds from the microphone.

13.   The sound of a departing troop-transport plane mingled with the popping sound of burning buildings.

14.   They sat quietly for a few minutes, until the lights dimmed and they heard a tremendous roar and a popping sound they thought was hail.

15.   We drew closer when an odd popping sound echoed from the direction of the airport.

16.   What is this popping sound, and how can I stop it?

17.   When you removed the stopper, it made a popping sound.

18.   When Reynolds flexes the muscles in his jaw, he can produce a popping sound, a sort of high-pitched whistle.

19.   When the seeds are ripe, the pod bursts open with an audible popping sound, broadcasting the new seeds a good distance from the original flower.

20.   With a balloon placed inside, the targets make a satisfying popping sound, and even collapse, when hit.