er (第11/20页)

　It　is　a　bat.　But　this　bat　looks　like　a　fox.　A　flying　fox　is　very　big.　It　likes　to　eat　fruit.　Sometimes　the　flying　fox　is　called　fruit　bat.

    The　flying　fox　flies　into　fruit　trees.　The　eats　all　the　fruit.　So　fruit　farmers　do　not　like　the　flying　fox.

    Passage　27.Flying　Birds

    Birds　don’t　fly　high　up　in　the　sky.　The　air　is　too　thin.

    It　is　hard　for　birds　to　breathe　in　thin　air.　Thin　air　doesn’t　hold　them　up.

    Birds　fly　he　ground　so　that　they　　see　where　they　are.　The　birds　look　for　pces　they　know.　Then　they　do　not　get　lost.　Some　birds　fly　so　low　over　the　o　that　the　waves　often　hide　them.　Many　birds　fly　a　long　distan　the　spring　and　autumn.

    Passage　28.Air

    Air　is　all　around　us.　It　is　around　us　as　we　walk　and　py.　From　the　time　we　were　born　air　is　around　us　on　every　side.　Whe　down，　it　is　around　us.　When　we　go　to　bed，　air　is　also　around　us.　We　live　in　air.　We　　live　without　food　or　water　for　a　few　days，　but　we　ot　live　for　more　than　a　few　minutes　without　air.　We　take　in　air.　When　we　are　w　or　running　we　need　more　air.　When　we　are　asleep，　we　need　less　air.　We　live　in　air，　but　we　ot　see　it.　We　　only　feel　it　when　it　is　moving.　Moving　air　is　called　wind.　How　　we　make　air　move?　Here　is　one　way.　Hold　an　open　book　in　front　of　your　face，　close　it　quickly.　What　　you　feel?　What　you　feel　is　air.

    Passage　29.Clocks

    There　are　many　clocks　in　the　Brown’s　house.　They　are　in　different　rooms.A　big　clock　stands　in　a　er　of　the　sitting　room.　It　is　a　very，　very　old　clock，　but　it　still　keeps　good　time.　Mr.　Brown　winds　it　once　a　week.

    Passage　30.　Swimming

    Swimming　is　a　good　sport.　It’s　popur.　People　like　swimming　because　the　water　makes　people　feel　cool.　But　if　they　swim　in　a　wrong　pce，　it　is　very　dangerous.　These　years，　some　people　died　when　they　were　enjoying　themselves　in　water　and　most　of　them　were　students.　Summer　holiday　will　be　there　again.　I　want　to　give　you　some　advice.　First，　don’t　get　into　the　water　when　yo