英语文章首字母填空、Batsaretheonlyflying"animals".Itisknowntoallthatcannotseeverywell."Asb___asabat"isoftenheard.Yet,theyhavenotroubleflingonthedarkestnightsandf___theirwayroundverywell.Whycanbatsflyan

　　英语文章首字母填空、

　　Batsaretheonlyflying"animals".Itisknowntoallthatcannotseeverywell."Asb___asabat"isoftenheard.Yet,theyhavenotroubleflingonthedarkestnightsandf___theirwayroundverywell.Whycanbatsflyandseeatnight?Theyflyby"radar".Thebat'sradarworksthesamewaya____theradaronshipsandplanes.Asabatfliesthroughtheair,itmakesasound.I____thesoundshitthings,thewillcomebackandthebat'searswillreceivethemessage.Inthisway,thebatcanknowwherethethingsare.Batsgoouforf___ainight.Inthedaytime,theyhanginsomedarkplaces.

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