ONE advantage of the English language is that you can get away with grammatical murder, as long as you never write anything down. James Dawson (Letters, 2 April) does us a service in pointing out the crass solecism "didn't used to" - a foolish error indeed, when the interviewee could, without any extra effort, have said the grammatically perfect "didn't use to", which sounds exactly the same! Wodehouse's aunts knew what they were at.

Martin Smith, Oxford