It is an old book.（改为复数形式） Have you ever been to america?（作否定回答） ...
问题描述：
It is an old book.（改为复数形式） Have you ever been to america?（作否定回答） ...
It is an old book.（改为复数形式） Have you ever been to america?（作否定回答） The lake is very beautiful.（改为何感叹句） (i have lost the bike.My grandfather bought it for me.) （两句合并成一定语从句） the children ran out.（改为倒装句） We have never heard of it.（改为倒装句）
答
1.They are old books.
2.No,I haven't.
3.How beautiful the lake is.
4.I have lost the bike that my grandfather bought it for me.
5.Ran out the children.
6.Never had we heard of it.