observationsn.观察值名词observation的复数形式.observationn.观察；观察力；注意；评论observation on spot现场观测observation of fire射击观测observation accuracy观测精度observation sentence情境句observation aircraft观察机observation of stage水位观测observation aperture观察孔径observation interval观测时间长度observation monument观测标志,测站标石observation practice认识实习