Because the river is not on the map.

因为地图上没有河。

This isn't on the map, but it's all clearly signposted.

地图上没有画，但是路上设有明显的路标。

Because the river is not on the map. - It's bound to go past a town.

因为地图上没有河 - 这条河肯定会流经村庄。

But back when Gilligan's Island was made, well, apparently there were some islands that were not on the map.

但是当 Gilligan's Island 被制作出来的时候，嗯， 显然有一些岛屿不在地图上。

This isn't on the map but it is all clearly signposted. You cross the field which spreads along the banks of the river.

这不在地图上，但是已经很清晰地标明在路标上。你跨过这块延伸到河岸的地。

But many of them have one thing in common: the people hit the hardest are often literally not on the map.

但他们中的许多人都有一个共同点：受灾最严重的人往往根本不在地图上。