He had been taking part in an international symposium on population.
他那时在参加一个有关人口的国际研讨会。
E. g. He had been taking part in an international symposium on population.
他那时正参加一个有关人口问题的国际研讨会。
A major event was the International Symposium on Intellectual Property and Information Technology 1999.
年内举行的一项盛事，是1999年知识产权与资讯科技国际研讨会。
A major event was the International Symposium on Intellectual Property and Information Technology 1999.
年内举行的一项盛事，是1999年知识产权与资讯科技国际研讨会。
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