单词	mc--maintenance center
释义	maintenance center，MC维护中心
随便看	observational definition observational equation observational error observational frequency observational learning observationally observationally equivalent observational method observational network observational point observational research observational site selection observational skill observational statement observational study observational twilight observation and learning activities observation angle observation angle (of a retroreflector) observation angle [of a retroreflector] observation apparatus observation aviation observation balloon observation battalion observation board