I feel really stupid for asking this but it's been bugging me for a week now. My daughter is in 1st grade and they are learning about nouns. On her homework, she had to fill in the blank with a noun. The sentence was basically this: ______ is my favorite color. So, my daughter inserts the word "Green." Green is my favorite color. And I'm thinking... wait, isn't green an adjective? After all, green is describing "my favorite color." But then I was like, wait a minute.... favorite is the adjective because it's describing color. Totally confused. Green is my favorite color. <---- How is 'Green' in this sentence considered a noun?