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 female student concentrates on her schoolwork.
Hypothesis: A student is at school working on her schoolwork.
Update: The library is very quiet and a good place for her to finish her assignment.
Example Output: strengthener

Example Input: Premise: Little boy in black jacket, kicking leaves.
Hypothesis: A child is happily playing in the leaves.
Update: His face is sullen.
Example Output: weakener

Example Input: Premise: A woman in elaborate beaded dress doing a dance.
Hypothesis: The woman dances very well.
Update: The woman is teaching a dance class.
Example Output:
strengthener