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来源:雅诚德英语网
Ultrasound is used by many animals that detect and some of them send out very high frequency sounds.
许多动物都用超声波来进行侦查,有些动物还能发出非常高频的声音。
Ultrasound is used by many animals that detect and some of them send out very high frequency sounds.
许多动物都用超声波来进行侦查,有些动物还能发出非常高频的声音。