participant用得比较多【participant】n.参加者，参与者； 与会代表； 参与国； 关系者adj.参加的； 有关系的【例句】1. 40 of the course participants are offered employment with the company...上这门课的人中有40个被该公司聘用。2. You are expected to be an active participant.你应该成为积极的参与者。3. The size of the conference was larger and there were more participants in it. 会议规模较大，参加人数较多。【participator】n.参与者，合作者【例句】1. This researching can be reference for project participator in project turn-key management. 本研究可供我国工程项目参与各方开展交钥匙承包参考。2. Part four is rights and duties of each Electronic Authentication Service participator. 电子认证服务各参与人的权利义务。最准确，请采纳，有问题追问，祝好！【来自英语牛人团】
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