vividness (n.) 鮮豔
The vividness of the animal’s feather attracts the children’s attention.
tweet (n.) 鳴叫
The bird tweets because it is hungry.
nutrient (n.) 營養
Nutrients are important for people.
artificial (adj.) 人工的
The flowers are artificial. Don't water them.
breeding (n.) 繁殖
Some female animals change their color during their breeding seasons.