Clearances
n. 清除( clearance的复数形式 ); 许可; （录用或准许接触机密以前的）审查许可; 净空
🗣️ 情景例句
Would you like anything else?
还要其他的吗？
Mike is already a junior.
迈克已经大学三年级了。
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。