Bays/Gulfs/Capes, Straits, Deserts

Please will you explain how you have decided which answers require the addition of the word strait, bay, desert etc and which don't? Because otherwise it is very hard for us to decide. Even harder to decide whether to call it Strait of Gibraltar (as is normal) or Gibraltar Strait. Again, please explain.

Better still, don't require the addition of these words at all.