1) You are not using my pen. / You're not using my pen. / You aren't using my pen.
2) I am not doing the washing up right now. / I'm not doing the washing up right now.
3) Listen, he is not playing the guitar. / Listen, he's not playing the guitar. / Listen, he isn't playing the guitar.
4) She is not having a coffee at this very moment. / She's not having a coffee at this very moment. / She isn't having a coffee at this very moment.
5) It is not snowing this afternoon. / It's not snowing this afternoon./ It isn't snowing this afternoon.
6) They are not getting married. / They're not getting married. / They aren't getting married.
7) The train is not leaving now. / The train's not leaving now. / The train isn't leaving now. / It is not leaving now. / It's not leaving now. / It isn't leaving now.
8) He is not shutting the windows. / He's not shutting the windows. / He isn't shutting the windows.
9) I am not taking the car to the garage. / I'm not taking the car to the garage.
10) Oh dear, he is not winning the race now. / Oh dear, he's not winning the race now. / Oh dear, he isn't winning the race now.