1.You are apostman（应该为postman）
否：You aren't postman.
疑：Are you postman?
肯答：Yes,I am.
否答：No,I'm not.
2.You are workers.
否：You aren't workers.
疑：Are you workers?
肯答：Yes,we are.
否答：No,we aren't.
3.We are in the park.
否：We aren't in the park.
疑：Are we in the park?
肯答：Yes,we are.
否答：No,we aren't.