translation.en: Now, it's important to remember that you're only hearing the human-audible parts of dolphin sounds, and dolphins make ultrasonic sounds, and we use special equipment in the water to collect these sounds.
translation.zh: 不过，别忘了你只听到了 人类能听到的那部分海豚声， 海豚们还会发出超声波， 我们在水中利用特殊器材 采集这些声音。