The bookcase isn’t for my sister.怎么改成肯定句

The bookcase isn’t for my sister.怎么改成肯定句 there isn't a bookcase in my study 变同义句 ____ ____ bookcase i there isn't a pencil.here's a pencil for you.（改成肯定句） there isn't any bread in the fridge.怎样改成肯定句 This isn't my mother(变肯定句) The pencil isn’t m___,it's my sister My sister doesn't have anew book(改为肯定句) My sister doesn't like strawberries【改为肯定句】 My sister doesn't like oranges.(改为肯定句） He isn't so tall as his sister改为肯定句 My father doesn't have a car改成肯定句怎么改? My sister doesn't like math.（改为肯定句） My sister _________ math