lighting light fixture illumination

[bosun]

What are the differnces between lighting, light fixtures and illluminations?
Can I say like

If your room is dark, place more light fixtures i(??)n your room because bad lighting(??) can make the rooms depressing.
.
If your room is dark, change lighting/light fixtures (??)to make your room brighter.

If your room is dark, add more illuminations (??)in your room.

(Which one sounds ok?

 

[IluvNY]

Bosun I would say: If your room is dark, add more lights as bad illumination can make the room depressing

Is that ok?

 

[vachecow]

Of the three you gave I think the first one is the best because I don't see how "changing" lights would make it much better, and "illuminations" is not very common.