H.L. Mencken (18801956). The American Language. 1921. 6. The
Noun The only inflections of the noun remaining in English are
those for number and for the genitive, and so it is in these two
regions that the few variations to be noted in vulgar American
occur. The rule that, in forming the plurals of compound nouns
or noun-phrases, the -s shall be attached to the principal noun
is commonly disregarded, and it goes at the end. Thus, I have
two sons-in-law is never heard among the plain people; one
always hears I have two son-in-laws. So with the genitive. I
once overheard this: that umbrella is the young lady I go withs.
Often a false singular is formed from a singular ending in s,
the latter being mistaken for a plural. Chinee, Portugee and
Japanee are familiar; I have also noted trapee, specie,93 tactic
and summon (from trapeze, species, tactics and summons).94
Paradoxically, the word incidence is commonly misused for
incident, as in he told an incidence. Here incidence (or
incident) seems to be regarded as a