circumnavigation的复数形式怎么写？

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circumnavigation的音标：circumnavigation的英式发音音标为：[ˌsɜ:kəmˌnævɪ'ɡeɪʃn]circumnavigation的美式发音音标为：[ˌsɜkəmˌnævɪ'ɡeɪʃn]...

Magellan's circumnavigation of the earth proved that it is a globe.麦哲伦周游世界的事实说明地球是圆的.Magellan's circumnavigation of the earth that it is a globe.麦哲伦的周游世界说明地球是圆的.Request circumnavigation ( to circumnavigate ) 30...