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. It makes you much less likely to believe the hypothesis is true. A strengthener is a statement that strengthens the hypothesis. It makes you much more likely to believe the hypothesis is true. Your task is to output 'strengthener' or 'weakener' if the update strengths or weakens the hypothesis, respectively.

Example Input: Premise: PersonX celebrates PersonY 's day
Hypothesis: Because PersonX wanted make person y happy
Update: They want them to return a favor
Example Output: weakener

Example Input: Premise: PersonX writes the book
Hypothesis: As a result, PersonX feels skillful
Update: PersonX does not like the book
Example Output: weakener

Example Input: Premise: PersonX realizes PersonY was lost
Hypothesis: As a result, PersonX feels concerned
Update: PersonY is lost in a large natural park.
Example Output:
strengthener