There are some dangerous fishes in this river, and I've warned Jack ________ here.

1. A.
   not to swim
2. B.
   to not swim
3. C.
   swim not to
4. D.
   to swim not

There are some dangerous fishes in this river, and I've warned Jack ________ here.

A. not to swim

B. to not swim

C. swim not to

D. to swim not