Our Living Language Some speakers of vernacular English varieties, particularly in isolated or mountainous regions of the Southern United States, use phrases such as of a night or of an evening in place of at night or in the evening, as in We'd go hunting of an evening. This of construction is used only when referring to a repeated action, where Standard English uses nights, evenings, and the like, as in We'd go hunting nights. It is not used for single actions, as in She returned at night. · These of and -s constructions are related. The -s construction, which dates back to the Old English period (c. 449-1100), does not signify a plurality but is similar to the so-called genitive suffix -s, which often indicates possession, as in the king's throne. Just as this example can also be phrased as the throne of the king, nights can be reformulated as of a night. This reformulation has been possible since the Middle English period (c. 1100-1500). Sometimes the original -s ending remains in the of construction, as in We'd walk to the store of evenings, but usually it is omitted. Using of with adverbial time phrases has not always been confined to vernacular speech, as is evidenced by its occurrence in sources ranging from the Wycliffite Bible (1382) to Theodore Dreiser's 1911 novel Jennie Gerhardt: "There was a place out in one corner of the veranda where he liked to sit of a spring or summer evening." · Using such of constructions reflects a long-standing tendency for English speakers to eliminate the case endings that were once attached to nouns to indicate their role as subject, object, or possessor. Nowadays, word order and the use of prepositional phrases usually determine a noun's role. Despite the trend to replace genitive -s with of phrases, marking adverbial phrases of time with of is fading out of American vernacular usage, probably because one can form these phrases without -s, as in at night.