Present perfect continuous: To show something started in the past and continued until now. "They have been talking for the last hour." "James has been teaching at the university since June." "We have been waiting here for over two hours!" Here is a conversation to help you understand the given tenses: person 1: "Wow, Tom has gotten stronger!"; person 2: "He has been playing tennis." person 1: "Where is Tom?"; person 2: "He is playing tennis." Person 1: "What was Tom doing earlier?"; person 2: "He was playing tennis." Person 1: "Why should Tom teach me about tennis?"; person 2: "He has played tennis." I hope it helps :)