The question of genuine communication problems arising from structural differences of this kind is not often seriously discussed, the assumption generally being that non-standard speakers can "understand" standard English presumably in the sense that in some hypothetical context-free situation they are able to assign the same semantic structure as a standard speaker to a given phonetic string. The reason for this assumption (which is noted here mainly to encourage readers to consider whether they them- selves hold it) is probably the constant dissemination of spoken and written standard English through the news media and the educational system. The possibility that some speakers do not "understand" standard English appears for the most part to be mooted only when their systems are so divergent that they may, like West Indian creole-speakers in England, or Black English-speakers in the United States, be thought of in some un- satisfactorily specified way as not being English speakers at all (Edwards,1979; Nelson and McRoskey, 1978). However, in a recent extensive study of the Hiberno-English perfect (associated with a larger study ofnon-standard English) John Harris refers to frequent misinterpretations by Hibemo- English speakers of such standard English utterances as