Which preposition to use with stutterings

for Occurrences 1%

"W-what are you st-stuttering for?

of Occurrences 1%

Aleacman now Peleca, another stream in Thessaly, turns cattle most part white, si polui ducas, L. Aubanus Rohemus refers that struma or poke of the Bavarians and Styrians to the nature of their waters, as Munster doth that of Valesians in the Alps, and Bodine supposeth the stuttering of some families in Aquitania, about Labden, to proceed from the same cause, "and that the filth is derived from the water to their bodies."

Which preposition to use with  stutterings