Complex sentence: Finishing his retribution against Suneo and Gian, Nobita goes back home while lamenting that Doraemon willl never return; to his surprise, his solution works and Doraemon suddenly returns, being allowed to without reason.
Split into simpler sentences: Finishing his retribution against Suneo and Gian, Nobita goes back home while lamenting that Doraemon willl never return. To his surprise, his solution works and Doraemon suddenly returns being allowed to without reason.