Recently I have heard both of the following sentences:
The previous mayor was a woman, wasn't she?
The mayor is male, isn't it?
These seem to me to bear a gender contradiction here; "the mayor" and "the previous mayor" are both non-gendered rôles, but the people whom I overheard in the pub were quite happily talking about these differently gendered situations, having lived in Britain all their lives.
All I can think is that this is some sort of colloquialism, or there is a difference between "is male" and "a woman".
Are either of these thoughts valid, and is there a genuine grammatical rule here or is it just a confusion caused by the current heatwave in the UK?
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Edit: By the sounds of it this was all a product of a good evening's drink and unusually hot weather. The response appears to have been as I would naturally say, that the usage of it was merely a slip of the tongue and that one should use he instead.