21.   This summer, Disneyland will have volunteers who roam the park day and night, turning out lights and replacing incandescent bulbs with more energy-efficient ones.

22.   Typical halogen light bulbs are smaller than traditional screw-in incandescent bulbs.

23.   A glass roof helps keep the cabin brighter, and fiber optic headlamps replace incandescent bulbs.

24.   Only incandescent bulbs are allowed in the house, because they produce less ultraviolet radiation.

25.   The lights company has contracted many chicken farms in Beijing and replaced the traditional incandescent bulbs with their CFLs at no cost to the farms.