the girl is playing the piano at the party 改成提问句,回答,否定句,一般疑问

哪部分提问?
否定句 The girl isn't playing the piano at the party.
一般疑问句 Is the girl playing the piano at the party?
再问： 没写。。 army day is on august 1st（on august 1st）提问
再答： What is the girl doing at the party? She is playing the piano at the party. When is the army day?
再问： army day is on august 1st（on august 1st）提问 这道题
再答： 就是When is the army day?