Evergreens are called "evergreens" because all evergreens are green all year long. They don't change color or shed their leaves.
Chrysanthemums, are a genus of about 30 species of perennial flowering plants in the family Asteraceae
a flower
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An evergreen tree. If the word begins in a vowel or consonant with a vowel sound, it is preceded by "an". If the word begins with a regular consonant, it begins with "a".