Mikawa
三河国（日本古代令制国之一）
🗣️ 情景例句
You're still thinking about something to do, aren't you?
你还在想要找点事做， 是吗？
Please come in and have a orange.
请进来吃一个桔子。
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。