I did some research and in japan theres a game
named Doki Doki Panic. Its about 2 kids reading a book and got sucked
in by a hand then 4 heros come and save them.AND
IN MARIO IT LOOKS EXACTLY THE SAME BACKGROUND!!!
Wow , interesting.....indeed Super Mario 2 suks major...
(Goes to the emulator to play "the lost levels" , wich i already have but i thought it was actually SM 1 levels.. so i never tryed..)
A modified Doki Doki Panic game IS the US version of Super Mario Brothers 2. They just changed a few things and modified the characters to Mario characters' sprites.