retain基本说一个人把某东西留下来了，比如你retain possession（保留所有权，比如物品或者足球的控制） remain可以用来说别人，请你remain在你的座位上等等 哎呀，总之最好的办法是多看看例句，然后就有语感了，‘就是知道’应该用哪个。再怎么解释，再用中文分析，也不如这 remain: 1.to continue to be in the same state or condition. Please remain seated until all the lights are on. 2.to stay in the same place without moving away. The refugees were allowed to remain in the UK. retain: 1.to keep something or continue to have something You have the right to retain possession of the goods. 2. to remember information: I find it very difficult to retain facts. 再不清楚了，借本韦氏近义词辨析词典查一下《Merriam Webster's Dictionary of Synonyms》。
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