Complex sentence: His energetic grandmother suggests he speak with the Once-ler, who, according to legend, will tell anyone about trees if brought fifteen cents, a nail, and a shell of great-great-great grandfather snail.
Split into simpler sentences: His energetic grandmother suggests he speak with the Once-ler about this. According to the tale Ted's grandmother mentions, the Once-ler will tell anyone about trees if brought fifteen cents, a nail, and a shell of great-great-great grandfather snail.