英语语法分析

The frequencies used in sonar systems vary from infrasonic to ultrasonic.

声纳所使用的频率从次声到超声不等。

In the first part, an infrasonic pressure chamber system was established.

第一部分为次声压力仓系统的建立及性能检测。

Another haunted and related natural phenomenon is known as frequency infrasonic sound waves.

另一种与闹鬼相关的自然现象是称作次声的低频声波。