我觉得我不会需要钱，但我会带一些以防万一。

I don't think I'll need any money but I'll bring some ___just ___in ___case.

带张地图以防你迷路。

Bring a map ___in ___case you get lost.

带上舒适的鞋子，以防你要走很多路。

Bring comfortable shoes ___in ___case you do a lot of walking.