With no explanation, label text_A→text_B with either "strengthener" or "weakener".
text_A: A defensive football player from Wisconsin almost sacking the UTEP quarterback before he got rid of the ball. A defensive football player from Wisconsin almost sacking the UTEP quarterback before he got rid of the ball, and the crowd behind them is cheering.
text_B: A sea of red and black is being very vocal.
strengthener.