It's wrong to solve equations in one direction and simply reject those that don't work, because the unrejected ones may not work either unless tested manually
@PVAL-inactive The word 'irregardless' appears in merriam-webster.com, but of course, it is marked as nonstandard and people are advised to use 'regardless' instead.
I think other than naturals including zero or not, there is also the issue of whether rings have one or not, how to define the fourier transform, and how to write subset and proper subset.
@Daminark I taught in some average schools here, and I can tell you this: The classroom behaviour is atrocious. The worst behaviour you see on TV is actually the best in reality.
@Piomicron 'Distaff' and 'counterpart' are both words. It depends on what you want to mean when you say them together. This also has nothing to do with GCSE or not.