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一渔船向鱼群发出超声波,若鱼群正向渔船靠近,则被鱼群反射回来的超声波与发出的超声波相比( )
要防患于未然,我们未成年人就应努力做到( )
— There's _________ important in today's newspaper, isn't there?— Sorry, I don't know. I haven't got the paper yet.