The word good is an adjective. Use good to describe or modify a noun.
Bob is a good boy.
I have good health.
Mark got a good grade on his test.
The word well is an adverb. Use well to tell more about an action.
Bob behaves well.
I feel well.
Mark did well on his test.
Remember to use the word good when modifying a noun. Use the word well when modifying a verb and telling more about an action.
▶It’s your turn. Choose either good or well for the blank in this sentence. Sarah plays the piano very ____. Did you choose the word that will modify the verb and tell how she plays? Good for you!