| 释义 |
upon 义务阶段1500 全国卷频次：17 /əˈpɔn/ prep. 在…上面；在…后，立即；即将来临；在…的时候、当…时，一…就… 高考真题原句提选：Father has left for London on business upon my arrival, so I didn’t see him.我刚到学校，父亲就去伦敦出差了，所以我没有见到他。When the explorers first set foot upon the continent of North America, the skies and lands were alive with an astonishing variety of wildlife.当探险家们第一次踏上北美大陆时，天空和大地充满了令人惊叹的各种野生动物。 |