Did not accept 'king' nor 'saint'. My guess is that you typed in 'kings'and 'saints', and the system works better if you go for shorter words.

Words that happen to be homophones isn't really a group, very tenuous - you could as easily have had Rabbit/Skyscraper/Shoe/Pimple on the grounds that they are all nouns. A nice distraction with the Isle of Wight's "Yarmouth", though, as it's obviously not as well known as the one in mainland Britain.

Groups are too vague, especially the homophones one

how is sauce a homphone ?