Anchor: Two girls are walking down the street, one of them has an umbrella.
Entailed: There are two girls walking down the street.
Contradiction: There are two girls sitting in the street.
Contradiction: The GAO may not offer any assistance to Congress at all.  
Contradiction: Poland was forced to adopt Soviet principles.
Contradiction: A man is ironing a shirt.
Contradiction: A boy jumps over boxes.