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 中国学生与美国学生,数学能力差距太大了。差距到底在哪里?https://t.co/BlBXquD0TS https://video.twimg.com/ext_tw_video/1772257512969924608/pu/vid/avc1/720x1280/7YifljxICPkyrUMF.mp4?tag=12