Complex sentence: Indebted to the Jedi, Jar Jar leads them to an underwater Gungan city where the Jedi try but fail to persuade the Gungans to help the people of Naboo, though they are able to obtain transportation to Theed, the capital city on the surface.
Split into simpler sentences: Indebted to the Jedi, Jar Jar leads them to an underwater Gungan city. There the Jedi try but fail to persuade the Gungans to help the people of Naboo, though they are able to obtain transportation to Theed, the capital city on the surface.