Are there any English verbs that are ambiguous with regard to their thematic roles, although they are the same on the surface?
To clarify, in John worries Mary, John causes the worries, but in John worries about Mary, John experiences the worries. I'd like to know whether there are also verbs that show the same pattern, but without a change in surface structure (the addition of about in this case). It's not necessary that one of the senses is causative.
One example I've found is speak to, but it doesn't work well in the sense of appeal to when the subject is a person, instead of, say, a painting.