Terragraph
地面立体测图仪
🗣️ 情景例句
Hey, what did you do on your trip?
嗨，旅游时玩的怎么样？
All of those men are friends of mine.
那些人的都是我的朋友。
and by measuring the time interval between the taps and the receipt of the echoes, the depth of the sea at that point can be calculated.
测出回声间隔的时间，便可算出该处海洋的深度。