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.
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Question: Premise: A man is moving a gate that impedes the progress of an oncoming train.
Hypothesis: The railroad worker is completing his last task for the day.
Update: The worker is very tired.

Answer: strengthener


Question: Premise: Two people standing in a curved interior, multi-level building.
Hypothesis: The people are standing in an elevator inside.
Update: People are standing inside curved multi-level building.

Answer: weakener


Question: Premise: A black dog runs on green grass towards the camera.
Hypothesis: The dog likes the feeling of the grass.
Update: The dog stays on the grassy area and wags his tail a lot.

Answer:
strengthener