帮我改肯定句、否定句、一般疑问句：He ate two burgers a moment ago.She danced and sang the day daybefore yesterday.I was a bad boy several years ago.They were very lovely in 2001.这些句子都要改.
问题描述：
帮我改肯定句、否定句、一般疑问句：He ate two burgers a moment ago.She danced and sang the day day
before yesterday.
I was a bad boy several years ago.
They were very lovely in 2001.
这些句子都要改.
答