Isn't there a bird on the desk?（回答有）
问题描述：
Isn't there a bird on the desk?（回答有）
回答没有一只鸟在桌子上
答
当做疑问句 Is there a bird on the desk?
回答有 Yes,there is.
回答是可以将回答补全 Yes,there is（a bird on the desk）.
No,there isn't（a bird on the desk）.