Roleset stammer.01 Verbnet Class: NONE "not speak clearly":

Roles:

Arg0:speaker


Arg1:utterance


Arg2:listener

Examples:

person: ns tense: past aspect: ns voice: active form: full


intransitive (-)
Amateur linguists note here that Pursewarden, in Durrell's Alexandria Quartet, stammered when he spoke of his wife, which is hardly surprising in view of their disastrous relationship.
Arg0:	Pursewarden
Argm-LOC:	in Durrell's Alexandria Quartet
REL:	stammered
Argm-TMP:	when he spoke of his wife
Argm-ADV:	which is hardly surprising in view of their disastrous relationship

person: ns tense: past aspect: ns voice: active form: full


with utterance (-)
She stammered, ``You heard what he said about police?''
Arg0:	She
REL:	stammered
Arg1:	``You heard what he said about police?''

person: ns tense: past aspect: ns voice: active form: full


with listener (-)
``I'm sorry,'' Mary stammered to John.
Arg1:	``I'm sorry''
Arg0:	Mary
REL:	stammered
Arg2-to:	to John

Not sure if arg2 will ever really appear.