Echometry
测回声术
🗣️ 情景例句
Just relax.
不用紧张。
A smart coat is a good letter of introduction.
人要衣装，佛要金装。
Their population has now increased to 435,000, and today they make up about 13% of the population.
不过现在他们的人口已增长到435，000人，如今他们已占全国人口的13%。