All I do all day is work and watch TV . I really should start thinking about my health .   I never thought about that , but you're right . What do you think we should do ?   For starters , we should start doing more outdoor activities . That way we'll get some exercise .   I was thinking about taking tennis lessons . I always have an hour to spare in the afternoon . What do you think about that ?   That's not a bad idea . How much is it ?   I heard it is only about one hundred twenty dollars a month for 8 lessons . 