Geoffrey Pullum, on a lacuna in English:
My preliminary experiments with dictionary searching suggest that English has absolutely no words with roots of forms like *bobbib, *papoop, *tettit, *doded, *keckick, *gaggig, *mimmom, *naneen, *faffiff, *sussis, etc. These are simple CVCVC shapes that do not seem to contain any un-English sequence. They aren't hard to say