The Pygmalion effect means that when someone gains the trust and expectations of others, they will have a positive motivation to work harder to achieve the expectations of others. Based on the above definitions, Which of the following are Pygmalion effects (). ["Wang Dong wanted to become the Olympic champion, and finally achieved his dream with the coach's rigorous training and his own efforts.", 'Xiaoming closed himself because of stuttering as a child, but with the encouragement and help of his parents, he grew up to become an excellent speaker.', 'Zhou, a student who lost the college entrance examination, was discriminated against by people around him and gave up.', 'Police Liu Liu, with the lofty ideal of serving the people, strives to meet the various requirements of the masses at work.']