VOA慢速英语:受过教育的警察是否不太可能使用武力？

college - n. a school in the U.S. that you go to after high school (often a university)

courage - n. the ability to do something that you know is difficult or dangerous

expose - v. to cause someone to experience something or to be influenced or affected by something

challenge - v. to test the ability, skill, or strength of someone or something

role - n. a part that someone or something has in a particular activity or situation

de-escalation - n. the decrease in the level of conflict in a situation

kneel - v. to move your body so that one or both of your knees are on the floor

valid - adj. fair or reasonable

reassure - v. to make someone feel less afraid, upset, or doubtful