With no explanation, label text_A→text_B with either "strengthener" or "weakener".
text_A: A dark-haired man in a striped shirt records a video of a gray-haired man using a MacBook laptop. The dark-haired man does not know the man who is using a laptop.
text_B: The grey-haired man is using Skype to call the police on the strange man filming him.
strengthener.