She questioned whosoever turn it was?

[GoesStation]

I don't think whosever has been widely accepted. I would not recommend it to learners.

 

[Phaedrus]

You can find "whosever" in unabridged dictionaries, in the OED, and in such usage manuals as Garner's Modern English Usage, including the fourth edition (2016).

 

[GoesStation]

A comprehensive unabridged dictionary includes all sorts of words that careful writers should avoid. However, Garner seems not only to accept whosever but to recommend it.

 

[Phaedrus]

Huddleston and Pullum discuss whosever and whoever's in a footnote on page 1075 of The Cambridge Grammar of the English Language (2002):

"The genitive forms whosever and (informal) whoever's are possible but rare in the free choice construction. Thus Take whosever/whoever's you like could serve as a response to the question Whose bicycle shall I take? The genitives are not admissible outside the free choice construction -- cf. *They want to question whosever/whoever's dog was barking throughout the night or *Whosever/Whoever's car is blocking my driveway must move it immediately. The close grammatical association between the genitive determiner and the following head noun seems to suggest the anomalous meanings where it is the dog they want to question and the car that must move itself."

-- CGEL, p. 1075

 

[GoesStation]

Some folks around here would resolve this by saying take everwho's you like.

Learners, this is nonstandard dialect, so you may admire it but you shouldn't adopt it.

 

[Tdol]

Huddleston and Pullum discuss whosever and whoever's in a footnote on page 1075 of The Cambridge Grammar of the English Language (2002):

In a footnote. It's quite a jump to recommending it willy-nilly.

 

[Phaedrus]

In a footnote. It's quite a jump to recommending it willy-nilly.

One small step for grammar. One giant leap for learner-kind.