a neutral colour scheme的用法和样例：
- As for backpack, I would prefer a neutral colour like black or white, perhaps on of the white attached pics.
- A neutral tie can be worn with a shirt of any colour.
- GREEN: Because of its association with nature and foliage, green in design can be used almost like a neutral colour: greens never clash with red or pink roses, yellow sunflowers, lilacs or bluebells.
- I don't like the colour scheme in their sitting-room.