Complex sentence: In the Bebi Saga of GT, Rou Dai Kaiôshin helps Goku to become much stronger by regrowing his tail, a painful process involving a giant set of pliars, and after Goku has his tail he is able to turn Super Saiyan 4 and defeat Bebi.
Split into simpler sentences: In the Bebi Saga of GT, Rou Dai Kaiôshin helps Goku become much stronger by regrowing his tail, a painful process involving a giant set of pliars. After Goku has his tail back, he is able to turn into a Super Saiyan 4 and defeat Bebi.