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.

Example Input: Premise: A boy in a black shirt punches a yellow punching bag while a boy in a blue sweatshirt holds the bag.
Hypothesis: Two boys take turns using a punching bag.
Update: They are both training.
Example Output: strengthener

Example Input: Premise: A woman is looking out the window.
Hypothesis: The woman is enjoying the view outside.
Update: The window looks out onto a flower-filled meadow.
Example Output: strengthener

Example Input: Premise: a man paddles his canoe on the lake.
Hypothesis: The man is going swimming.
Update: The man is barefoot in swim trunks.
Example Output:
strengthener