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.

Premise: A young man goes air-born while his skateboard spins underneath him.
Hypothesis: The man is not wearing a helmet.
Update: His hair is flying in front of his face.
strengthener

Premise: A smiling man with short brown hair in a black shirt with an open orange shoe box.
Hypothesis: The man is buying new shoes.
Update: The shoe box holds a big pile of receipts.
weakener

Premise: Two males are sitting on a dock, one of which is playing guitar, and another two are standing in front of them.
Hypothesis: Two men are creating entertainment for money.
Update: He is teaching them how to play a guitar.

weakener