Пример:
Anna /play the guitar/piano
Anna isn't playing the guitar
She's playing the piano
1)Alexey and Anna /play chess/tennis
..........................................
2)Natasha /write /paint
..........................................
3) Elena /write a letter /write an e-mail
..........................................
Alexey and Anna aren't playing chess. they are playing tennis.Natasha isn't writing. she is painting.Elena isn't writing a letter. she is writing an e-mail