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: Two men wearing sunglasses and walking outside.
Hypothesis: The two men are siblings.
Update: The men have different parents.
Example Output: weakener

Example Input: Premise: A young african boy skipping rocks.
Hypothesis: There is a rock currently skipping down a pond.
Update: There are several expanding sets of rings on the surface of the pool.
Example Output: strengthener

Example Input: Premise: The children play with sparklers at night.
Hypothesis: The children were having a lot of fun with the sparklers
Update: The children are laughing.
Example Output:
strengthener