@vindex message-subject-trailing-was-regexp
Controls what to do with trailing @samp{(was: <old subject>)} in subject
lines. If @code{nil}, leave the subject unchanged. If it is the symbol
-@code{ask}, query the user what do do. In this case, the subject is
+@code{ask}, query the user what to do. In this case, the subject is
matched against @code{message-subject-trailing-was-ask-regexp}. If
@code{message-subject-trailing-was-query} is @code{t}, always strip the
trailing old subject. In this case,