walk out. some places remain submerged. that's why the divers have to put these boys into full face masks. there were 18 divers working inside the cave and they did in the this configuration. a diver would go up front carrying the air supply for the boy and tetters to the boy in the middle. they would follow a line out and another diver would come in the back to backstop the entire effort as they went through tight areas and other areas as we well. how many places are underwater we don't know. by some estimates, a quarter of this cave may still require that passage. the boys have to go under 11 football fields completely underwater with muck and cold and currents. it's a huge challenge but they got four of them out. why did they stop? they ran out of their oxygen supply. but the clock is really ticking