Input: 

The most surprising news story of the past week must be the 'wonderful' story that the AIDS epidemic in India is under control.

Sentence: The most surprising news story of the past week must be the 'terrible' story that the AIDS

Output: No


Input: 

While preliminary work goes on at the Geneva headquarters of the WTO, with members providing input, key decisions are taken at the ministerial meetings.

Sentence: Decisions are not made at the Geneva Headquarters 

Output: Yes


Input: 

He also referred to the "illegal" arrest on 31 May of Mexican Professor Maria Eugenia Ochoa Garcia, whom the Salvadoran government accused of having connections with the Salvadoran guerrillas.

Sentence: Maria was implied to have connections with the Salvadoran guerrillas

Output: Yes


Input: 

Lunch with friends<br>Amy and Nora went to the new Mexican place for lunch. They both ordered giant Margaritas and chips and salsa. Amy enjoyed a burrito and Nora had delicious fish tacos. While they were eating, a mariachi band came to their table. Before they left, they tipped the band because they were so good.

Sentence:  Amy and Nora tipped the waiter.

Output:
It's impossible to say