Resposta:
1- Negativa: I wasn't buying hot dog yesterday
Interrogativa: Was I buying hot dog yesterday?
2-Negativa:Charles wasn't writing a new book
Interrogativa: Was Charles writing a new book?
3-Negativa: My brother wasn't playing ball
Interrogativa:Was my brother playing ball?
4-Negativa: She and I weren't making the lesson
Interrogativa: Were she and I making the lesson?
5-Negativa:Stephanie wasn't swimming at the club
Interrogativa:Was Stephanie swimming at the club?