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.

Q: Premise: Four people wearing red, blue, white& black, walking up a white staircase overlooking a marina in an old city.
Hypothesis: The group of people are all part of a party.
Update: They are returning children on Halloween who wore matching costumes while trick or treating.

A: weakener
****
Q: Premise: Two swimmers competing in swim competition.
Hypothesis: The swim competition is held inside
Update: The swimmers swim under some bright lights on the ceiling.

A: strengthener
****
Q: Premise: A old man wearing blue is throwing rocks at the ocean.
Hypothesis: An old man is skipping stones in the ocean.
Update: The man throws a stone and watches as it bounces along the surface.

A:
strengthener
****