1) He gave me five hundred dollars to take care of his dog.
I think there is a weird kind of ambiguity in that sentence. One idea is obviously that he paid me so that I would take care of his dog.
The other idea is (very unlikely but possible):
2) He gave me five hundred dollars to take care of his dog with.
In this case, the money doesn't go into my pocket. He isn't paying me anything. I am probably taking care of his dog as a favor. The money is to be spent on the dog,
Is there ambiguity or not?
Gratefully,
Navi