instruction:
In this task, you are given a premise, a hypothesis, and an update. The premise sentence describes a real-world situation and is always assumed to be true. The hypothesis sentence describes an assumption or inference that you might make about that situation having read the premise. The update provides additional information about the situation that might weaken or strengthen the hypothesis. A weakener is a statement that weakens the hypothesis, that is, it makes you much less likely to believe the hypothesis is true. A strengthener is a statement that strengthens the hypothesis, that is, it makes you much more likely to believe the hypothesis is true. Your task is to answer with 'strengthener' or 'weakener' if the update strengthens or weakens the hypothesis, respectively.
question:
Premise: A man on a motorcycle is towing a bicyclist on his bicycle behind him.
Hypothesis: A man on a red motorcycle is towing a bicyclist on a blue bicycle.
Update: The bicyclist's black helmet matches the color of his bike.
answer:
weakener


question:
Premise: A man in a gray t-shirt, hat and jeans, cutting a circle in the sidewalk, with an audience of men in the background.
Hypothesis: The men in the T-shirt is cutting a hole for a manhole in the sidewalk.
Update: The hole isn't over a sewer.
answer:
weakener


question:
Premise: Trees obscure a building to the right.
Hypothesis: There are trees near that building.
Update: Fallen leaves are on the building.
answer:

strengthener