My learned followers will probably think I’m be teaching my grandmother to suck eggs, but I heard someone using ‘less’ instead of ‘fewer’ on a documentary recently and it reminded me of how I first learned the distinction.
The best way I know to remember the difference is that fewer refers to things you can count (fewer words in the manuscript, fewer replies from publishers) and less is used for things that can’t be counted (less sand on the beach, less pollution in the air).
It always makes me think of how were taught the distinction by our English teacher at much-missed High Pavement Grammar School, EWN Smith (known as Compass Face – geddit?) He said that if you were at a football match where not so many spectators had turned up this week and said ‘There are less people here today’, the literal meaning would be that the people were smaller than at the last game. I’m not sure that’s strictly true, and I may have misremembered his exact words, but it has served me in good stead over the years!