到PETS 2级听力原文及答案2007年03月-2013年09月PETS 2级听力原文及答案practiced and insincere.Finally comes “The Robot”a small,thin smile lacking in warmth.The group also warns against smiling too quickly,saying it can make you look false.The best smile,they say,is slowerand flows naturally across the whole face.KEYS TO THE LISTENING TESTS (200703-201309)