Double "is"

by Mark Israel
 
     [This is a fast-access FAQ excerpt.]

Double "is", as in "The reason is, is that..." is a recent U.S.
development, much decried.  According to MEU3, it was first noticed
in 1971 and had spread to the U.K. by 1987.  Of course, "What this
is is..." is undisputedly correct.