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来源:雅诚德英语网
Their instruments detected very faint radio waves at a frequency of 3 kilohertz.
他们的仪器探测到了频率为3千赫的非常微弱的无线电波。
Their instruments detected very faint radio waves at a frequency of 3 kilohertz.
他们的仪器探测到了频率为3千赫的非常微弱的无线电波。