Acervulus
[医] 脑沙, 松果体石
🗣️ 情景例句
Could be.
也许。
The lumberjack sweats as he cuts down a tree.
伐木工人边砍树边擦汗。
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。