John's team performs well this season. John's - the apostrophe to show possession (the team belonging to John) Also, you must use "well" instead of "good" in this sentence since "well" is an adverb while "good" is an adjective. As you probably know, an adverb describes a verb and the verb you are describing in this sentence is "perform". Good luck! :)

John's team is performing well this season. When you want to express belonging use the possessive apostrophe. In this case John belongs to this team. It is his team.