The word good is an adjective. Use the word good to modify a noun.
Bobby is a good boy.
That was a good dinner.
I have a good idea.
The word well is an adverb. Use the word well to tell more about the action.
Bill performed well at the track meet.
We ate well while vacationing on the cruise ship.
My dog behaves well at obedience school.
Use the adjective good to modify a noun. Use the adverb well to modify a verb and tell more about the action.
▶It’s your turn. Decide whether to put good or well into this sentence blank. My sister sings _____. Did you choose the word that will modify a verb? Good for you!