Ответ:

  1. You are in my class. Negative: You aren't in my class. Question: Are you in my class?
  2. It is a nice day. Negative: It isn't a nice day. Question: Is it a nice day?
  3. I am 14 years old. Negative: I am not 14 years old. Question: Am I 14 years old?
  4. Your cousins are in Russia. Negative: Your cousins aren't in Russia. Question: Are your cousins in Russia?
  5. We are partners. Negative: We aren't partners. Question: Are we partners?