dà / dì / shuǐ / zhǔn / miàn / shì / cè / liáng / hǎi / bá / gāo / dù / shí / shǐ / yòng / de / zhòng / yào / cān / kǎo / miàn大地水准面是测量海拔高度时使用的重要参考面。The geoid is an important reference surface used when measuring elevation.