You will be given a context and a verb separated with a newline character, and you have to answer if the given verb is a negation or not. A verb is a negation if it is not going to exist, not happen, or has no effect. The output should be "Yes" if the verb is a negation and "No" otherwise.

NAIROBI, Kenya ( AP ) _ U.S. Secretary of State Madeleine Albright paid tribute Tuesday to bombing victims and embassy staffers on a whirlwind visit to East Africa, and promised to (track) down the perpetrators.
Verb: track
No

When asked if she thought the boy's father, Juan Miguel Gonzalez, was being controlled by the Cuban government even though he has been in Bethesda, Md., for the last week, she frowned. I do n't (know) what Juan Miguel thinks or believes, Juanita Castro said.
Verb: know
Yes

DPC last week launched a new, $10-a-share offer for the Woodland Hills, Calif. - based computer printer maker. DPC said it could n't (comment) on the suit.
Verb: comment
Yes