【正确答案】The lecture is about a psychological concept called peer reinforcement. The professor presents a case study of a kindergarten student named Sarah to illustrate this concept.
According to the lecture, Sarah did not play well with others. She also did not pick up her toys after playing or stop playing when the time for play ended. And she never listened to her teachers. So one of her teachers praised another obedient pupil in front of Sarah and even asked them to play together. Soon the girl acted much more like her peer. She picked up her toys and stopped playing on time. So the example of her peer was more effective than the teacher's words.

【答案解析】[听力原文]
M: Yes, I know that today's reading of peer reinforcement was slow going. But as we know, psychologists usually take ordinary actions and make the theory behind them seem strange and mysterious. Seriously, though, an example of peer reinforcement should make everything pretty clear.
There was a kindergarten pupil, let's call her Sarah. She did not obey the class rules for play and interfered with other children. She also would not pick up building blocks after playing with them and sometimes went on playing after play time had ended. Her teachers, of course, told her to play nicely and to pick up the blocks. But, yep that's right. In one ear and out the other, she did not listen and did not obey.
So one of the teachers noticed there was a boy in class named Paul. Paul always played nicely, picked up his blocks, and stopped playing when told to stop. So the teacher changed the strategy by praising Paul in front of Sarah and even had Paul and Sarah play with each other. Quickly, Sarah started acting more like Paul. She picked up her blocks, and she stopped playing on time. So, you see, the example of her peer Paul was more effective in correcting Sarah's behavior than anything her teacher could say. Or, at any rate, Paul's example, PLUS what the teacher said were enough to correct Sarah's misbehaving.

Alternative Wording(替换表达)
Synonyms (a)praise—commend, extol (b)obedient—compliant
(c)effective—fruitful
Paraphrases 1. Her teachers'commands were ineffective.
2. The girl quickly followed her peer's lead.