'whatever he prefers' is a correct and usable phrase in written English.
You could use it in a sentence such as, "I'm happy to do whatever he prefers".
With the Mets paying him a sizable amount this season, Bay can take whatever offer he prefers, even if that offer is only for the league minimum, which is probably the type of offer he's going to get.
"Viewed together, Obama's policies have certainly led us to this dangerous point in Iraq and Syria, but Paul's brand of isolationism (or whatever term he prefers) would compound the threat of terrorism even further," Perry wrote.
Though there are further technical conditions to extend the theory to infinite sets of alternatives and to capture further plausible rationality conditions concerning gambles, economists generally subscribe to a view of a rational agent as possessing complete and transitive preferences and as choosing among the feasible alternatives whatever he or she most prefers.
Once again, so much for Obama's ludicrous assessment of Isis as "the jayvee team" of whatever it was he preferred to call jihadism.
Mrs. Clinton has already been broadcasting an ad highlighting crude remarks from Mr. Trump about women; she answered his taunts about her marriage with a rhetorical shrug, telling reporters Mr. Trump was free to run whatever kind of campaign he preferred.
So the Pareto front contains a wealth of information and can provide decision makers with whatever they prefer to choose.
Always call the person by whatever they prefer, whether that is "Miss Smith", "Lily", or even just "Ma'am".
Try giving them an object to manipulate in one hand as they work, such as a squishy stress ball, a tangle, a little beanbag, or whatever they prefer.
"Whatever you prefer," he said, as if there were really a choice.
When I ask him what language we should speak, he says, "Whatever you prefer".
