on多用於系統論述或專題講演、論著等，具有學術性，如：The teacher told us a story about Lei Feng. It"s very moving. He will give us a talk on the history of the Party.他將給我們做個關於黨史的報告。
正誤例析 今天下午我們將聽一個關於非洲歷史的演講。
誤：We"re going to listen to a lecture about African history his afternoon.
正：We"re going to listen to a lecture on African history this afternoon.
簡單區分，about通俗大眾；on學術【專業】性強
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on與about 二者都是介詞，意為“關於，論及”等，一般情況下，二者可以互相替換，但二者有點區別：about常用於簡單的或淺顯的論述等，是一般用語，多用於講故事，談話；思考等；
on多用於系統論述或專題講演、論著等，具有學術性，如：The teacher told us a story about Lei Feng. It"s very moving. He will give us a talk on the history of the Party.他將給我們做個關於黨史的報告。
正誤例析 今天下午我們將聽一個關於非洲歷史的演講。
誤：We"re going to listen to a lecture about African history his afternoon.
正：We"re going to listen to a lecture on African history this afternoon.
析：介詞about和on都可以作“關於”解。on表示一本書、文章或演講是嚴肅的、學術性的，可供專門研究這一問題的人們參考；about則表示其內容比較通俗，一般人都可閱讀。