coloration

他的演讲带有明显的乐观色彩。

His speech had an optimistic ___coloration.

这只蝴蝶翅膀上的色彩组合非常迷人。

The ___coloration on this butterfly's wings is truly fascinating.

这只蝴蝶翅膀上鲜艳的色彩能吓退捕食者。

The butterfly's bright ___coloration on its wings helps scare away predators.